CBSE Class 10 Science Metals And Non Metals Notes

Download CBSE Class 10 Science Metals And Non Metals Notes in PDF format. All Revision notes for Class 10 Science have been designed as per the latest syllabus and updated chapters given in your textbook for Science in Class 10. Our teachers have designed these concept notes for the benefit of Class 10 students. You should use these chapter wise notes for revision on daily basis. These study notes can also be used for learning each chapter and its important and difficult topics or revision just before your exams to help you get better scores in upcoming examinations, You can also use Printable notes for Class 10 Science for faster revision of difficult topics and get higher rank. After reading these notes also refer to MCQ questions for Class 10 Science given on studiestoday

Revision Notes for Class 10 Science Chapter 3 Metals and Nonmetals

Class 10 Science students should refer to the following concepts and notes for Chapter 3 Metals and Nonmetals in Class 10. These exam notes for Class 10 Science will be very useful for upcoming class tests and examinations and help you to score good marks

Chapter 3 Metals and Nonmetals Notes Class 10 Science

METALS AND NON-METALS       

7.1 INTRODUCTION:

There are 118 chemical elements known at present. One the basis of their properties, all these elements can be broadly divided into two main groups: Metals and Non-Metals. A majority of the known elements are metals. All the metals are solids, except mercury, which is a liquid metal. There are 22 non-metals, out of which, 10 non-metals are solids, one non-metal (bromine) is liquid and the remaining 11 non-metals are gases.

7.2 POSITION OF METALS AND NON-METALS IN THE PERIODIC TABLE :

The metals are placed on the left hand side and in the centre of the periodic table. One the other hand, the non-metals are placed on the right hand side of the periodic table. This has been shown in the figure. It may be noted that hydrogen (H) is an exception because it is non-metal but is placed on the left hand side of the periodic table.

Metals and non-metals are separated from each other in the periodic table by a zig-zag line. The elements close to zig-zag line show properties of both the metals and the non-metals. They show some properties of metals and some properties of non-metals. These are called metalloids. The common examples of metalloids are boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te) and polonium (Pi)

class_10_science_concept_0206

In general, the metallic character decreases on going from left to right side in the periodic table. However, on going down the group, the metallic character increases. 

The elements at the extreme left of the periodic table are most metallic and those on the right are least metallic or non-metallic.

7.3  GENERAL PROPERTIES OF METALS AND NON-METALS :

7.3 (a) Electronic Configuration of Metals :

The atoms of metals have 1 to 3 electrons in their outermost shells. For example, all the alkali metals have one electron in their outermost shells (lithium 2, 1; sodium 2,8,1: potassium 2,8,8,1 etc.)

Sodium, magnesium and aluminium are metals having 1,2 and 3 electrons respectively in their valence shells. Similarly, other metals have 1 to 3 electron in their outermost shells.

It may be noted that hydrogen and helium are exception because hydrogen is a non-metal having only  electron in the outermost shell (K shell) of its atom and helium is also a non-metal having 2 electron in the outermost shell (K shell).

7.3 (b) Physical Properties of Metals:

The important physical properties of metals are discussed below:

(i) Metals are solids at room temperature: All metals (except mercury) are solids at room temperature.

MERCURY is a liquid at room temperature.

(ii) Metals are malleable: metals are generally malleable. Malleability means that the metals can be beaten with a hammer into very thin sheets without breaking. Gold and silver are among the best malleable metals. Aluminium and copper re also highly malleable metals.

(iii) Metals are ductile : It means that metals can be drawn (stretched) into this wires. Gold and silver are the most ductile metals. Copper and aluminium are also very ductile, and therefore, these can be drawn into this wires which are used in electrical wiring.

(iv) Metals are good conductors of heat and electricity: All metals are good conductors of heat. The conduction of heat is called thermal conductivity. Silver is the best conductor of heat. Copper and aluminium are also good conductors of heat and therefore, they are used for making household utensil. Lead is the poorest conductor of heat. Mercury metal is also poor conductor of heat.

Metals are also good conductors of electricity. The electrical and thermal conductivities of metals are due to the presence of free electrons in them. Among all the metals, silver is the best conductor electricity. Copper and aluminium are the next best conductors of electricity. Since silver is expensive, therefore, copper and aluminium are commonly used for making electric wires.

(v) Metals are lustrous and can be polished: Most of the metals have shine and they can be polished. The shining appearance of metals is also known as metallic lustre. For example, gold, silver and copper metals have metallic lustre.

SILVER is best conductor of heat and electricity.

(vi) Metals have high densities : Most of the metals are heavy and have high densities. For example, the density of mercury metal if very high (13.6 g cm-3). However, there are some exceptions. Sodium, potassium, magnesium and aluminium have low densities. Densities of metals are generally proportional to their atomic masses. The smaller the metal atom, the smaller it its density.

(vii) Metals are hard : Most of the metals are hard. But all metals are not equally hard. Metals like iron, copper, aluminium etc. are quite hard. They cannot be cut with a knife. Sodium and potassium are common exceptions which are soft and can be easily cut with a knife.

(viii) Metals have high melting and boiling points : Most of the metals (except sodium and potassium) have high melting and boiling points.

Notes: Tungsten has highest melting point (34100C) among all the metals.

(ix) Metals are rigid : Most of the metals are rigid and they have high tensile strength.

(x) Metals are sonorous: Most of the metals are sonorous i.e., they make sound when hit with an object.

7.3 (c) Electronic Configuration of Non-Metals :

The atoms and non-metals have usually 4 to 8 electrons in their outermost shells. For example, Carbon (At. No6), Nitrogen (At. No. 7), Oxygen (At. No.8 ), Fluorine (At. No. 9) and Neon (At. No. 10) have respectively 4,5,6,7,8 electrons in their outermost shells.

7.3 (d) Physical Properties Of Non-Metals:

The important physical properties of non-metals are listed below :

 (i)  Non-metals are brittle.

(ii) Non- metals are not ductile.

(iii) Non-metals are bad conductor of heat and electricity. (Exception: Graphite is a good conductor because of the presence of free electrons.)

(iv) Non-metals are not lustrous and cannot be polished. (Exception: Graphite and Iodine are lustrous non- metals.)     

(v) Non-metals may be solid, liquid, or gases at room temperature. 

(vi) Non-metals are generally soft. (Exception: Diamond, an allotropic from of non-metal Carbon, is the hardest natural substance known). 

(vii) Non-metals have generally low melting and boiling points. (Exception: Graphite another allotropic form of Carbon, has a melting point of about 37300C).           

(viii) Non-metals have low densities. (Exception : Iodine has high density).          

Graphite is a good conductor of electricity, lustrous and has very high melting point.    

7.3 (e) Chemical Properties of Metals :

The atoms of the metals have usually 1, 2 or 3 electrons in their outermost shells. These outermost electrons are loosely held by their nuclei. Therefore, the metal atoms can easily lose their outermost electrons to from positively charged ions. For example, sodium metal can lose outermost one electron to form positively charged ions, Na+. After losing the outermost electron, it gets stable electronic configuration of the noble gas (Ne : 2, 8 ), Similarly, magnesium can lose two outermost electron to from Mg2+ ions and aluminium can lose its three outermost electrons to from Al3+ ions.

class_10_science_concept_0207

 

 

 

 

 

 

The metal atoms lose electrons and form positively charged ions, therefore, the metals are called electropositive elements.

Some of the important chemical properties of metals are discussed below :

(i) Reaction with oxygen : Metals react with oxygen to from oxides. These oxides are basic in nature. For example, sodium metal reacts with oxygen of the air and form sodium oxide.

class_10_science_concept_0208

Sodium oxide reacts with water to form and alkali called sodium hydroxide. Therefore, sodium oxide is a basic oxide.

class_10_science_concept_0209

Due to the formation of sodium hydroxide (which is an alkali), the solution of sodium oxide in water turns red litmus blue (common property of all alkaline solutions).

When metal oxides are dissolved in water, they give alkaline solutions.

Similarly, magnesium is a metal and it reacts with oxygen to form magnesium oxide. However, magnesium is less reactive than sodium and therefore, heat is required for the reaction.

class_10_science_concept_0210

Thus, when a metal combines with oxygen, it loses its valence electrons and forms positively charged metal ions. We can say that oxidation of metal takes palace.

Reactivity of metals with oxygen:

All metals do not react with oxygen with equal ease. The reactivity of oxygen depends upon the nature of the metal. Some metals react with oxygen even at room temperature, some react on on heating  while still others react only on strong heating.

For example :

(A) Metals like sodium, potassium and calcium react with oxygen even at room temperature to form their oxides.

class_10_science_concept_0211

(B) Metals like magnesium and zinc do not react with oxygen at room temperature. They burn in air only on strong heating to from corresponding oxides.

class_10_science_concept_0212

(C) Metals like iron and copper do not burn in air even on strong heating. However, they react with oxygen only on prolonged heating.

class_10_science_concept_0213

(ii) Reaction with water : Metals react with water to form metal oxide or metals hydroxide and hydrogen. The reactivity of metals towards water depends upon the nature of the metals. Some metals react even with cold water, some react with water only on heating while there are some metals do not react even with steam. For example,

(A) Sodium and potassium metals react vigorously with cold water to form sodium hydroxide and hydrogen gas is liberated.

class_10_science_concept_0214

The reaction between sodium and water is so violent that the hydrogen evolved catches fire.

(B) Calcium reacts with cold water to form calcium hydroxide and hydrogen gas. The reaction is less violent.

class_10_science_concept_0215

 (C) Magnesium reacts very slowly with cold water but reacts rapidly with hot boiling water forming magnesium oxide and hydrogen.

class_10_science_concept_0216

 (D) Metals like zinc and aluminum react only with steam to form their corresponding oxides oxide hydrogen.

class_10_science_concept_0217

(E) Iron metal does not react with water under ordinary conditions. The reactions occurs only when steam is passed over red hot iron and the products are iron (II, III) oxide and hydrogen. 

class_10_science_concept_0218

(F) Metals like copper, silver and gold do not react with water even under strong conditions. The order of reactivities of different metals with water is :

Na >Mg >  AI > Zn   > Fe    > Cu

Rectivity with water decreases

(iii) Reaction with dilute acids : Many metals react with dilute acids and liberate hydrogen gas. Only less reactive metals such as copper, silver, gold etc. do into liberate hydrogen from dilute acids. The reactions of metals with dilute hydrochloric acid (HCI) and dilute sulphuric acid (H2SO4) are similar. With dil. HCI, they given metal chlorides and hydrogen whereas with dil. H2SO4, they give metal sulphates and hydrogen

Dilute nitric acid (HNO3) is an oxidising agent which oxidises metals, but does not produce hydrogen.

The reactivity of different metals is different with the same acid. For example:

(A) Sodium, magnesium and calcium react violently with dilute hydrochloric acid (HCI) or dilute sulphuric acid (H2SO4) liberating hydrogen gas and corresponding metal salt.

class_10_science_concept_0219

class_10_science_concept_0220

Therefore copper is even less reactive that iron

The order of reactivity of different metals with dilute acid:

Na       >          Mg       >          AI        >          Zn        >          Fe        >          Cu

Reactivity with dill acids decreases from sodium to copper.

(iv) Reactions of metals with salt solutions: When a more reactive metals is placed in a salt solution of less reactive metal, then the more reactive metal displaces the less reactive metal from its salt solution. For example, we will take a solution of copper sulphate (blue coloured solution) and put a strip of zinc metal in the solution. It is observed that the blue colour of copper sulphate fades gradually and copper metals are deposited on the zinc strip. this means that the following reaction occurs :

class_10_science_concept_0221

Here, zinc displaces copper from its salt solution.

However, if we take zinc sulphate solution and put a string of copper metal in this solution, no reaction occurs.

class_10_science_concept_0222

This means that copper cannot displace zinc metal from its solution. Thus, we can conclude that zinc is more reactive than copper. However, if we put gold or platinum strip in the copper sulphate solution, then copper is not displaced by gold or platinum. Thus, gold and platinum are less reactive than copper.

7.4 REACTIVITY SERIES OF METALS:

7.4 (a) Introduction:

We have learnt that some metals are chemically very reactive while others are less reactive or do not react at all.

On the basis of reactivity of different metals with oxygen, water acids as well as displacement reactions, the metals have been arranged in the decreasing order of their reactivities.

The arrangement of metals in order of decreasing reactivities is called reactivity series or activity series of metals.

The activity series of some common metals is given in Table. In this table, the most reactive metal is placed at the top whereas the least reactive metal is placed at the bottom. As we go down the series the chemical reactivity of metals decreases.

class_10_science_concept_0223

7.4 (b) Reasons for Different Reactivities:

In the activity series of metals, the basis of reactivity is the tendency of metals to lose electrons. If a metals can lose electrons easily to form positive ions, it will react readily with other substances. Therefore, it will be a reactive metal. On the other hand, if a metal loses electrons less rapidly to form a positive ion, it will react slowly with the other substances. Therefore, such a metal will be less reactive. For example, alkali metals such as sodium and potassium lose electrons very readily to from alkali metal ions, therefore, they are very reactive.

7.4 (c) Displacement of Hydrogen from Acids by Metals :

All metals above hydrogen in the reactivity series (i.e. more active than hydrogen) like zinc, magnesium, nickel can liberate hydrogen from acids like HCI and H2SO4. These metals have greater tendency to lose electrons than hydrogen. Therefore, the H+ ions in the acids will accept electrons and give hydrogen gas

as :

class_10_science_concept_0224

The metals which are below hydrogen in the reactivity series (i.e. les reactive than hydrogen) like copper, silver, gold cannot liberate hydrogen form acids like HCI, H2SOetc. These metals have lesser tendency to lose electrons than hydrogen. Therefore, they cannot lose electrons to H+ ions.

7.4 (d) Reactivity Series and Displacement Reactions :

The reactivity series can also explain displacement reactions. In general, a more reactive metal (placed higher in the activity series) can displace the less reactive metal from its solution. For example, zinc, displaces copper form its solution.

            Zn (s) + CuSO4 (aq) → ZnSO4 (aq) + Cu(s)

7.4 (e) Usefulness of Activity Series:

The activity series is very useful and it gives the following information:

(i) The metal which is higher in the activity series is more reactive than the other. Lithium is the most reactive and platinum is the least reactive.

(ii) The metals which have been placed above hydrogen are more reactive than hydrogen and these can displace hydrogen from its compounds like water and acids to liberate hydrogen gas.

(iii) The metals which are placed below hydrogen are less reactive than hydrogen and these cannot displace hydrogen from its compounds like water and acids.

(iv) A more reactive metal (placed higher in the activity series) can displace the less reactive metal from its solution.

(v) Metals at the top of the series are very reactive and, therefore, they do not occur free in nature. The metals at the bottom of the series are least reactive and, therefore, they normally occur free in nature. For example, gold, present in the reactivity series is found in Free State in nature.

8.1 HOW METALS REACT WITH NON-METALS :

Octet Rule : Octet rule was given by G.N. Lewis and W.Kossel in 1916.

According to actet rule “an atom whose outermost shell contains 8 electrons (octet) is stable.”

This rule, however, does not hold good in case of certain small atoms like helium (He) in which presence of 2 electrons (duplet) in the outermost shell in considered to be the condition of stability.

Examples of elements whose atoms have fully filled or 8 e- in their outermost shell are –

class_10_science_concept_0225

All noble gases contain 8 valence electrons (except He in which 2 valence electrons are present) and are stable. They do not usually form bonds with other elements.

Atoms combine with one another to achieve the inert gas electron arrangement and become stable. Atoms from chemical bonds to achieve stability by acquiring the inert gas configuration or by completing their octet or duplet (in case of small atoms) in outermost shell. An atom can achieve the inert gas electron arrangement in three ways -

(i)  by losing one or more electrons .

(ii) by gaining one or more electrons.

(iii) by sharing one or more electrons.

Noble gases do not usually from bonds with other elements. because they are stable. So. atoms of elements have the tendency to combine with one another to achieve the inert gas configuration.

8.2  CONCEPT OF IONIC BOND :

Except the elements of group 18 of the periodic table all the elements for the remaining group, at normal temperature and pressure, are not stable in independent state. These elements from stable compounds either by combining with the other atoms or with their own atoms. When in gross electronic configuration of the elements there are 8 electrons present then these elements do not take part in the chemical reaction because atoms containing 8 electrons in their outermost shell are associated with extra stability and less energy.

Atoms with other electronic configuration, which do not contain eight electrons in their outermost shell, are unstable and to achieve the stability they chemically combine in such a manner that they achieve eight electrons in their outermost shell. 

Two or more than two types of atoms mutually combine with each other to achieve stable configuration of eight valence electrons. Attempt to achieve eight electrons in the outermost orbit of a element is the reason behind its chemical reactivity or chemical bonding.

8.3  IONIC OR ELECTROVALENT BOND:

This bond is formed by the atoms of electropositive and electronegative elements. Electropositive elements lose electrons in chemical reaction and electronegative elements gain electrons in chemical reaction. When an atom of electropositive element come in contact with that of an electronegative element then the electropositive atom loses electron & becomes positively charged, while the electronegative atom gains the electron to become negatively charged. Electrostatic force of attractions works between the positively and negatively charged ions due to which both ions are bonded with each other. As a result, a chemical bond is produced between the ions, which is known as Ionic or Electrovalent compound.

Number of electrons donated or accepted by any element is called Electrovalence.

In an ionic compound every cation is surrounded by a fixed number of anions and every anion is surrounded by a fixed number of cations and they are bonded in a fixed geometry in a three dimensional structure.

Example : Sodium chloride compound.

Sodium atom (Electropositive element) by losing an electron from its outermost orbit, gets converted into a cation and attains noble gas like stable configuration.

Energy required for this process is called “ionization potential.”

class_10_science_concept_0226

Chlorine atom (Electronegative element) accepts the electron donated by sodium atom in its outermost orbit and forms chloride anion.

 In this process energy is released which is known as “electron affinity.”

class_10_science_concept_0227

Due to the opposite charges on the Na+ and CI- ions, they are bonded by electrostatic force of attraction to from NaCI compound.

class_10_science_concept_0228

Here electrovalent of sodium and chlorine atom is one.

For the formation of ionic bond, it is necessary that the ionization potential of electropositive element should be less and the electron affinity of electronegative element should be high.

8.3 (a) Properties of Ionic Compounds:

(i)  Ionic compounds consist of ions: All ionic compounds consist of positively and negatively charged ions and not molecules. For example, sodium chloride consists of Na+ and CI- ions, magnesium fluoride consists of Mg2+ and F- ions and so on.

(ii) Physical nature : Ionic compounds are solid and relatively hard due to strong electrostatic force of attraction between the ions of ionic compound.

(iii) Crystal structure : X-ray studies have shown that ionic compounds do not exist as simple single molecules as Na+CI-, This is due to the fact that the forces of attraction are not restricted to single unit such as Naand CI- but due to uniform electric field around and ion, each ion is attracted to a large number of other ions. For example, one Na+ ion will not attract only one CI- ion but it can attract as many negative charges as it an. Similarly, the CIion will attract several Na- ions. As a result, there is a regular arrangement of these ions in three dimensions as shown in diagram. Such a regular arrangements is called crystal lattice.

class_10_science_concept_0229

(iv) Melting point and boiling point : Strong electrostatic force of attraction if present between ions of opposite charges. To break the crystal lattice more energy is required so their melting points and boiling points are high.

(v) Solubility : Ionic compounds are generally soluble in polar solvents like water and insoluble in no - polar solvents like carbon tetrachloride, benzene, ether alcohol etc.

(vi) Brittle nature: Ionic compounds on applying external force or pressure are broken into small pieces, such substances are known as brittle and this property is known as brittleness. When external force is applied on the ionic compound, layers of ions slide over one another and particles of the same charge come near to each other as a result due to the strong repulsion force, crystals of compounds are broken.

class_10_science_concept_0230

(vii) Electrical conductivity : Electrical conductivity in any substance is due to the movement of free electrons of ions. In metals electrical conductivity is due to the free movement of valency electrons. As ionic compound exhibits electrical conductivity due to the movement of ions either in the fused state or in the soluble state in the polar solvent. But in the solid state due to strong electrostatic force of attraction free ions are absent so they are insulator in the solid state.

9.1  OCCURRENCE OF METALS :

All metals are present in the earth’s crust either in the free state or in the form of their compounds. Aluminium is the most abundant metal in the earth’s crust. The second most abundant metal is iron and their one is calcium.

9.1 (a) Native and Combined State of Metals :

Metals occur in the crust of earth in the following two states -

(i)  Native state of free state: A metal is said to occur in a free or a native state when it is found in the crust of the earth in the elementary or uncombined form.

The metals which are very uncreative (lying at the bottom of activity series) are found in the free state. These have no tendency to react with oxygen and are not attacked by moisture, carbon dioxide of air or other no-metals. Silver, copper, gold and platinum are some examples of such metals.

(ii) Combines state : A metal is said to occur in a combined state if it is found in nature in the form of its compounds. e.g. Sodium, magnesium etc. Copper and silver are metals which occur in the free state as well as in the combined state.

9.2  MINERALS AND ORES :

The natural substances in which metals or their compounds occur either in native state or combined state are called minerals.

The minerals are not pure and contain different types of other impurities. The impurities associated with minerals are collectively known as gangue or matrix.

The mineral from which the metal can be conveniently and profitably extracted, is called an ore.

For example, aluminium occurs in the earth’s crust in the form of two minerals, bauxite (AI2,O3. 2H2O) and caly (AI2O3. 2SiO2. 2H2O). Out of these two, aluminium can be conveniently and profitably extracted from bauxite. So, bauxite is an are of aluminium.

 Oxygen is the most abundant element on earth’s crust.

9.2 (a) Types of Ores :

The most common ores of metals are oxides, sulphides, carbonates, sulphates, halides, etc. In general, very uncreative metals (such as gold, silver, platinum etc.) occur in elemental form or Free State.

(i)  Metals which are only slightly reactive occur as sulphides (e.g., CuS, Pbs etc.).

 (ii) Reactive metals occur as oxides (e.g., MnO2,  AO2Oetc.)

(iii) Most reactive metals occur as salts as carbonates, subparts, halides etc.

SOME COMMON ORES ARE LISTED IN THE TABLE

class_10_science_concept_0231

9.3  METALLURGY:

The process of extracting pure metals from their ores and then refining them for use is called metallurgy.

In other words, the process of metallurgy involves extraction of metals from their ores and then refining them from use. The ores generally contain unwanted impurities such as sand, stone, earthy particles, limestone, mica, etc., these are called gangue or matrix.

The process of metallurgy depends upon the nature of the ore, nature of the metals and they types of impurities present. Therefore, there is not a single method for the extraction of all metals. However, most of the metals can e extracted by a general procedure which involves the following steps.

Various steps involved in metallurgical processes are -

(a) Crushing and grinding of the ore.           

(b) Concentration of the ore or enrichment of the ore.           

(c) Extraction of metal from the concentrated ore.           

(d) Refining or purification of the impure metal.

 These steps are briefly discussed below -

9.3 (a) Crushing and Grinding of Ore :

Most of the ores occur as big rocks in nature. They are broken into small pieces with the help of crusher. These pieces are then reduced to fine powder with the help of a ball mill or a stamp mill. 

9.3 (b) Concentration of Ore or Enrichment of Ore :

The process of removal of unwanted impurities (gangue) from the ore is called ore concentration or ore enrichment.

(i) Hydraulic washing (washing with water) :

Principle: This method is based upon the difference in the densities of the ore particles and the impurities (gangue).

Ores of iron, tin and lead are very heady and, therefore, they are concentrated by this method.

(ii) Front floatation process:

Principle: this method is based on the principle of difference in the wetting properties of the ore and gangue particles with water and oil.

 This method is commonly used for sulphide ores.

(iii) Magnetic separation :

Principle: This method depends upon the difference in the magnetic properties of the ores and gangue.

This method is used for the concentration of haematite, an ore of iron.

The froth floatation process if commonly used for the sulphide ores copper, zinc, lead etc.

10.1 EXTRACTION OF THE METAL FROM THE CONCENTRATED ORE :

The metal is extracted from the concentrated ore by the following steps :

(a) Conversion of the concentrated ore into its oxide : The production of metal from the concentrated ore mainly involves reduction process. This can be usually done by two processes known as calcination and roasting process. The method depends upon the nature of the ore.

(b) Conversion of oxide to metal y reduction process

10.1 (a) Conversion of Ore into Metal Oxide :

 These are briefly discussed below :

(i) It is the process of heating the concentrated ore in the absence of air.

The calcination process is used for the following changes :

  1.  to convert carbonate ores into metal oxide.
  2.  to remove water from the hydrated ores.
  3.  to remove volatile impurities from the ore.

class_10_science_concept_0232

(ii) RoastingIt is the process of heating the concentrated ore strongly in the presence of excess air.

This process is used for converting sulphide ores to metal oxide. In this process, the following changes take place :

  1. the sulphide ores undergo oxidation to their oxides.
  2. moisture is removed
  3. volatile impurities are removed.          

For example :

class_10_science_concept_0233

Calcination is used for hydrated and carbonate ores and roasting is used for sulphide ores.

10.1 (b) Conversion of Metal Oxide to Metal:

The metal oxide formed after calcination or roasting is converted into metal by reduction. The method used for reduction of metal oxide depends upon the nature and chemical reactivity of metal.

The metals can be grouped into the following three categories on the basis for their reactivity:

  1. Metals of low reactivity.
  2. Metals of medium reactivity.
  3. Metals of high reactivity.

These different categories of metals are extracted by different technique. the different steps involved in separation are as follows :

(i) Reduction by heating : Metals placed low in the reactivity series are very less reactive. They can be obtained from their oxides by simple heating in air.

class_10_science_concept_0234

(ii) Chemical Reduction (For metals in the middle of the reactivity series):

The metals n the middle of the reactivity series, such as iron, zinc, lead, copper etc. are moderately reactive. These are usually present as sulphides or carbonates. Therefore, before reduction the metal sulphides and carbonates must be converted to oxides. This is done by roasting and calcination. The oxides of these metals cannot be reduced by heating alone. Therefore, these metal oxides are reduced to free metal by using chemical agents like carbon, aluminium, sodium or calcium.

(A) Reduction with carbon : The oxides of moderately reactive metals (occurring in the meddle of reactivity series) like zinc, copper, nickel, tin, lead etc. can be reduced by using carbon as reducing agent.

class_10_science_concept_0235

class_10_science_concept_0236

One disadvantage of using carbon as reducing agent is that small traces of carbon are added to metal as impurity. Therefore, it contaminates the metals.

Coke is very commonly used as a reducing agent because it is cheap.

(B) Reduction with carbon monoxide: Metals can be obtained from oxides by reduction with carbon monoxide in the furnace.

class_10_science_concept_0237

(C) Reduction with aluminiumCertain metal oxides are reduced by aluminium to metals.

class_10_science_concept_0238

Reduction of metals oxides with aluminium is known as aluminothermy or thermite process.

(iii) Reduction of electrolysis or electrolytic reduction : The oxide of active metals (which are high up in the activity series) are very stable and cannot be reduced by carbon or aluminium. These metals are commonly extracted by the electrolysis of their fused salts using suitable electrodes. This is also called electrolytic reduction i.e. reduction by electrolysis.

For example, aluminium oxide is very stable and aluminium cannot be prepared by reduction with carbon. It is prepared by the electrolysis of molten alumina (AI2O3).

class_10_science_concept_0239

It may be noted that during electrolytic reduction of molten salts, the metals are always obtained at the cathode (negative electrode).

The process of extraction of metals by electrolysis process is called electrometallurgy.

10.2  PURIFICATION OR REFINING OF METALS :

The metal obtained any of the above methods is usually impure and is known as crude metal. The process of purifying the crude metal is called refining.

10.2 (a) Liquation :

This method is use for refining the metals having low melting points, such as tin, lead, bismuth etc. This is based on the principle that the metal to be refined is easily fusible (melt easily (but the impurities do not fuse easily.

10.2 (b) Distillation:

This method is used for the purification of volatile metals (which form vapours readily) such as mercury and zinc.

10.2 (c) Electrolytic Refining :

This is most general and widely used method for the refining of impure metals. Many metals such as copper, zinc, tin, nickel, silver, gold etc. are refined electrolytic ally. It is based upon the phenomenon of electrolysis. In this method, the crude metal is cast into thick rods and are made as anodes, while the thin sheets of pure metal are made as cathodes, An aqueous solution of some salt of the metal is used as an electrolyte. On passing current through the electrolyte, the pure metal from the anode dissolves into the electrolyte. An equivalent amount of pure metal from the electrolyte is deposited on the cathode. The soluble impurities go in the solution whereas the insoluble impurities settle down at the bottom of the node and are known as anode mud. In this way, the pure metal from anode goes into electrolyte and from electrolyte it goes to the cathode

class_10_science_concept_0240

In electrolytic refining impure metal is made anode and pure metal is made cathode.

Zone refining and Van Arkel method are used for obtaining metals (Si, Ge etc.) of very high purity for certain specific applications.

11.1 CORROSION OF METALS :

Surface of many metals is easily attacked when exposed to atmosphere. The react with air or water  present in the environment and form undesirable compounds  on their surface. These undesirable compounds are generally  oxides.

Thus, corrosion is a process of deterioration of metal as a result of its reaction with air or water (present in environment) surrounding it.

11.1 (a) Corrosion of Iron:

iron corrodes readily when exposed to moisture and gets covered with a brown flaky substance called rust.  This is also called Rusting of Iron. Chemically, the rust if hydrated iron (III) oxide,  Fe2O3.XH2O. Rusting is an oxidation process  in which iron metal is slowly oxidized by the action of air (in presence of water). Therefore, rusting of iron takes place under the following conditions :

  1. Presence of air (or oxygen)
  2. Presence of water (moisture)           

More the reactivity of the metal, the more will be the possibility of the metal getting corroded.

(i) Experiment to show that rusting of iron requires both air and water -

We take three test tubes and put one clean iron nail in each of the three test tubes :

(A) In the first test tube containing iron nail, we put some anhydrous calcium chloride to absorb water (or moisture) from the damp air present in the test tube and make it dry.

(B) In the second test tube containing iron nail, we put boiled water because boiled water does not contain any dissolved air or oxygen in it. A layer of oil is put over boiled water in the test tube to prevent the outside air from mixing with boiled water.

(C) In the third test tube containing an iron nail, we put unboiled water so that about two-third of the nail is immersed in water and the rest is above water exposed to damp air.

After one week, we observe the iron nails kept in all the three test tubes.

class_10_science_concept_0241

(ii) We will obtain the following observations from the experiment :

(A) No rust in seen on the surface of iron nail kept in dry air in the first test tube. This tells us that  rusting of iron does not takes place in air alone.

(B) No rust is seen on the surface of iron nail kept in air free boiled water in the second test tube, This tells us that rusting of iron does not take place in water alone.

(C) Red brown rust is seen on the surface of iron nail kept in the presence of the air and water in the third test tube. This tells us that rusting of iron takes place in the presence of both air and water together.

(iii) Prevention of rusting

(A) Corrosion of metals can be prevented by coating the metal surface with a thin layer of pant, varnish or grease.

(B) Iron is protected from rusting by coating it with a thin layer of another metal which is more reactive that iron. This prevents the loss of electrons from iron because the active metal loses electrons in process of covering iron with zinc is called galvanization.  Iron is also coated with other metals such as tin known as tin coating.

(C) By alloying: Some metals when alloyed with other metals become more resistant to corrosion. For example, when iron is alloyed with chromium and nickel, it form stainless steel. This is resistant to corrosion and does not rust at all.

(D) To decrease rusting of iron, certain antirust solutions are used. For example, solutions of alkaline phosphates are used as antirust solutions.

11.1 (b) Corrosion of Aluminum :

Due to the formation of a dull layer of aluminum oxide when exposed to moist air, the aluminum metal loses its shine very soon after use. This aluminum oxide layer is very tough and prevents the metal underneath from further corrosion (because moist air is not able to pass through this aluminum oxide layer). This means sometimes corrosion is useful.

11.1 (c) Corrosion of Copper

When a copper object remains in damp air for a considerable time, then copper reacts slowly with carbon dioxide and water of air to form a green coating of basic copper carbonate [CuCO3, Cu(OH(2] on the surface of the object. Since copper metal is low in the reactivity series, the corrosion of copper metal is very, very slow.

11.1 (d) Corrosion of Silver :

Silver is a highly uncreative metal, so it does not reacts with oxygen of air easily. But, air usually contains a little of sulphur compounds such as hydrogen sulphide gas (H2S), which react slowly with silver to form a black coating of silver sulphide (Ag2S). Silver ornaments gradually turn black due to the formation of a thin silver sulphide layer on their surface and silver is said to be tarnished.

11.2 ALLOYS :

An alloy is a homogenous mixture of two or more metals or a metal and a non-metal. For example, iron is the most widely used metal. But it is never used in the pure form. this is because iron is very soft and stretches easily when not. But when it is mixed with a small amount of carbon (about 0.05%), it becomes hard and strong. The new form of iron is called steel.

11.2 (a) Objective of Ally Making :

Alloys are generally prepared to have certain specified properties which are not possessed by the contituent metals. The main objects of ally-making are :

(i) To increase resistance to corrosionFor example, stainless steel is prepared which has more resistant to corrosion than iron.

(ii) To modify chemical reactivity : The chemical reactivity of sodium is decreased by making an alloy with mercury which is known as sodium amalgam.

(iii) To increase the hardness: Steel, an alloy of iron and carbon is harder than iron.

(iv) To increase tensile strength: Magnesium is an alloy or magnesium and aluminum.

It has greater tensile strength as compared to magnesium and aluminum.

(v) To produce good casting: Type metal is an alloy of lead, tin and mercury.

(vi) To lower the melting point: For example, solder is an alloy of lead and tin (50) Pb and 50% Sn). It has a low melting point and is used for welding electrical wires together.

11.2 (b) Some Important Alloys :

 The approximate composition and used of some important alloys are given below :

(i) Steel :  Steel is an alloy of iron and carbon containing 0.1 to 1.5% carbon. Steel is very hard, tough and strong. It is used for making rails, screws, girders, bridges, railway lines etc. Steel can also be used for the contraction for building, vehicles, ships etc.

(ii) Allow Steels : Steel obtained by the addition of some other elements such as chromium, vanadium, titanium, molybdenum, manganese, cobalt or nickel to carbon steel are called Ally Steel.

(iii) Alloys of Aluminum : This common alleys of aluminum are :

(A) Duralumin. It is an alloy containing aluminum, copper and traces of magnesium and manganese. Its

percentage composition is - AO\I  95%, Cu = 4%, Mg = 0.5 % Mn = 0.5 % It is stronger than pure aluminum, Since duralumin is light and yet strong, it is used for making bodies of aircrafts, helicopter, jets and kitchenware’s like pressure cookers etc.

(B) Magnesium.  It is an alloy of aluminum and magnesium having the composition: Al - 95%, Mg = 5% It is very light and hard. It is more hard than pure aluminum. It is used for making light instruments, balance beams, pressure cookers etc.

(C) Alnico . It is an alloy containing aluminum, iron nickel, and cobalt. It is highly magnetic in nature and can be used for making powerful magnets.

(iv) Alloys of Copper:  The important alloys of copper are Brass and Bronze.

(A) BrassIt is an alloy of copper and zinc having the composition = Cu = 80% Zn = 20% Brass is more malleable and more strong than pure copper. It is used for making cooking utensils, condenser sheets, pipes, hardware, nuts, bolts, screws, springs etc.

(B) Bronze - It is an alloy of copper and tin having the composition : Cu = 90% Sn = 10% Bronze is very though and highly resistant to corrosion. It is used for making utensils, statues, cooling pipes, coins, hardware etc.

(C) German Silver - It is an alloy of copper, zinc and nickel having the composition: Cu = 60%, Zn = 20%, Ni = 20%. It is used for making silverware, utensils and for electroplating.

(v) Alloying of Gold : Pure gold is very soft and cannot be used as such for jewellery. Therefore, it is generally alloyed with other metals commonly copper or silver to make it harder and modify its colour. The purity of gold is expressed as carats. Pure gold is of 24 carat. A 18 carat gold means that is contains 18 parts of gold is 24 parts by weight of alloy. Most of the jewellery is made of 22 carat gold.

Amalgams are homogenous mixtures of a metal and mercury. For example, sodium amalgam contains sodium and mercury.

Different amalgams are prepared according to their used. For example,

(i) Sodium amalgam is produced to decrease the chemical reactivity of sodium metal. It is also used as a good reducing agent.

(ii) Tin amalgam is used for silvering cheap mirrors.

(iii) The process of amalgamation is used for the extraction of metals like godl or silver from their native ores.

 

 

GIST OF THE LESSON

Elements are classified broadly into two categories on the basis of properties:

Metals: Iron, Zinc, Copper, Aluminium etc. Non – metals: Chlorine, Nitrogen, Hydrogen, Oxygen, Sulphur etc. Apart from metals and non-metals some elements show properties of both metals and non – metals, e.g. Silicon, Arsenic, Germanium .They are called metalloids

class_10_science_concept_1

class_10_science_concept_1a

class_10_science_concept_1b

CBSE Class 10 Science Metals And Non Metals Notes Set C

Properties of ionic compounds
1. Physical nature:solid and hard due to strong force of attraction. (generally brittle)
2. Melting point and boiling point:have high M.P and B.P, as large amount of heat energy is required to break strong ionic attraction.
3. Solubility: soluble in water and insoluble in kerosene and pertrol.
4. Conduction of electricity:ionic compounds in solid state-----does not conduct electricity.
Reason—Ions can not move due to rigid solid structure. Ionic compounds conduct electricity in molten state.
Reason-- Ions can move freely since the electrostatic forces of attraction between the oppositely charged ions are overcome due to heat.

METALS AND NON – METALS Concepts

METALS AND NON – METALS Concepts

METALS AND NON – METALS Concepts

METALS AND NON-METALS

About 118 elements are known today. There are more than 90 metals, 22 non metals and a few metalloids.

Sodium (Na), potassium (K), magnesium(Mg), aluminium(Al), calcium(Ca), Iron(Fe), Barium(Ba) are some metals. Oxygen(O), hydrogen(H), nitrogen(N), sulphur(S), phosphorus(P), fluorine(F), chlorine(Cl), bromine(Br), iodine(l) are some non-metals

Physical properties of metals:

Solid at room temperature except mercury

Ductile (drawn into wires)

Malleable (beaten into thin sheets)

Sonorous(produce sound)

Lustrous(natural shine)

Have high melting point. Cesiumand galliumhave very low melting point.

Generally good conductor of heat and electricity, except lead and mercury which are comparatively poor conductors. Silver and copper are best conductors.

Have high density. Sodium and potassium can be cut with knife, they have low density.

Physical properties of non-metals:
• Occur as solid or gas. Bromine is liquid.
• Generally bad conductors of heat and electricity. Graphite a natural form of carbon is a good conductor.
• Non-lustrous, only iodine has lustre.
• Metals form basic oxides like Magnesium oxide(MgO), while non-metals form acidic oxides (as in acid rain).
*Chemical properties of metals:
1. Reaction with air
Metals can burn in air, react or don't react with air.
Metal + oxygen → Metal Oxide
• Some metals like Na and K are kept immersed in kerosene oil as they react vigorously with air and catch fire.
• Some metals likeMg,Al, Zn, Pb react slowly with air and form a protective layer.
• Mg can also burn in air with a white dazzling light to form its oxide
• Fe and Cu don't burn in air but combine with oxygen to form oxide.When heated iron filings burn when sprinkled over flame.

CBSE Class 10 Science Metals And Non Metals Notes Set A

CBSE Class 10 Science Metals And Non Metals Notes Set A

Try Balancing these Chemical equations yourself

3. Reaction with dilute acids:
Metal + dilute acid → Salt + Hydrogen gas

Metals react with dilute hydrochloric acid and dilute sulphuric acid to form
salt and hydrogen gas.
Fe + 2HCl → FeCl2 + H2
Mg + 2HCl→ MgCl2 + H2
Zn + 2HCl → ZnCl2 + H2
2Al + 6HCl → 2AlCl3 + 3H2

Copper, mercury and silver don’t react with dilute acids.
Hydrogen gas produced is oxidised to water when metals react with nitric acid. But Mg and Mn, react with very dilute nitric acid to evolve hydrogen gas.
Mg + 2HNO3 → Mg(NO3)2 + H2

4. Reaction of metals with other metal salts :

                 Salt           Salt
Metal A + solution → solution + Metal B
                of B             of A
All metals are not equally reactive. Reactive metals can displace less reactive metals from their compounds in solution. This forms the basis of reactivity series of metals.
Reactivity series is a list of metals arranged in order of their decreasing activities. 
cbse-class-10-science-metals-and-non-metals-notes-set-a

Reaction between Metals and Non-Metals :

– Reactivity of elements can be understood as a tendency to attain a completely filled valence shell.
– Atom of metals can lose electrons from valence shells to form cations (+ve ions).
– Atom of non-metals gain electrons in valence shell to form anions (–ve ions).
– Oppositely charged ions attract each other and are held by strong electrostatic forces of attraction forming ionic compounds.
cbse-class-10-science-metals-and-non-metals-notes-set-a

cbse-class-10-science-metals-and-non-metals-notes-set-a

Properties of Ionic Compounds :
– Are solid and mostly brittle.
– Have high melting and boiling points. More energy is required to break the strong inter-ionic attraction.
– Generally soluble in water and insoluble in kerosene, petrol.
– Conduct electricity in solution and in molten state. In both cases, free ions are formed and conduct electricity.

Occurance of Metals
Minerals : elements of compounds occuring naturally are minerals.
ORES : mineral fromwhichmetal can be profitably extracted is an ore. For example, sulphide ore, oxide ore, carbonate ore.
– Metals at the bottom of activity series like gold, platinum, silver, copper generally occur in free state. But copper and silver also occur in sulphide and oxide ores.
– Metals ofmediumreactivity (Zn, Fe, Pb etc.) occurmainly as oxides, sulphides or carbonates.
– Metals of high reactivity (K, Na, Ca, Mg andAl) are very reactive and thus found in combined state.
GANGUE : ores are naturally found mixed impurities like soil, sand, etc. called gangue. The gangue is removed from the ore.
METALLURGY : step-wise process of obtaining metal from its ore.
*Enrichment of ore
*Obtaining metal from enriched ore.

Extracting Metals Low in the Activity Series :
By heating the ores in air at high temperature.
*Mercury from cinnabar 
cbse-class-10-science-metals-and-non-metals-notes-set-a
– In the above reaction molten iron is formed and is used to join railway tracks.
This is called thermit reaction.

Extracting Metals at the Top of Activity Series :
These metals
– have more affinity for oxygen than carbon.
– are obtained by electrolytic reduction. Sodium is obtained by electrolysis of
its molten chloride NaCl  → Na+ + Cl
As electricity is passed through the solution metal gets deposited at cathode and non-metal at anode.
– At cathode :
Na+ + e → Na
– At anode :
2Cl → Cl2 + 2e–

Refining of Metals :

– Impurities present in the obtainedmetal can be removed by electrolytic refining.
Copper is obtained using this method. Following are present inside the electrolytic tank.
– Anode – slab of impure copper
– Cathode – slab of pure copper
– Solution – aqueous solution of copper sulphate with some dilute sulphuric acid
– From anode copper ions are released in the solution and equivalent amount of copper from solution is deposited at cathode.
– Impurities containing silver and gold gets deposited at the bottom of anode as anode mud.
cbse-class-10-science-metals-and-non-metals-notes-set-a

Corrosion :
– Metals are attacked by substances in surroundings like moisture and acids.
– Silver - it reacts with sulphur in air to form silver sulphide and articles become black.
– Copper - reacts with moist carbon dioxide in air and gains a green coat of copper carbonate.
– Iron-acquires a coating of a brown flaky substance called rust. Both air and moisture are necessary for rusting of iron.

Prevention of corrosion:
– Rusting of iron is prevented by painting, oiling, greasing, galvanizing, chrome plating, anodising and making alloys.
– In galvanization, iron or steel is coated with a layer of zinc because zinc is preferably oxidized than iron.

Alloys :

– These are mixture of metals with metals or non-metals  Adding small amount of carbon makes iron hard and strong.
– Stainless steel is obtained bymixing iron with nickel and chromium. It is hard and doesn’t rust.
– Mercury is added to other metals to make amalgam.
Brass : alloy of copper and zinc.
Bronze : alloy of copper and tin.
– In brass and bronze, melting point and electrical conductivity is lower than that of pure metal.
Solder : alloy of lead and tin has low melting point and is used for welding electrical wires.

METALS AND NON-METALS IN BRIEF

– Metals are generally solid, sonorous, lustrous, good conductor of heat and electricity, malleable, ductile, high melting point, high densities, form basic oxides, form +vely charged ion.
– Non-metals are generally solid or gas, non-lustrous, non-sonorous, bad conductor of heat and electricity, have low melting point, form acidic oxides and form -vely charged ions.
– Metals like Na, K and Ca are highly reactive, while others likeMagnesium, Aluminium, Zinc and Lead are less reactive and some others are least reactive like silver, gold and platinum.
– Metals generally displace hydrogen from acids.
– Reactivity series is based on displacement capability of metals and is a series of metals in the order of their decreasing reactivity.
– Metals and non-metals react to form ionic compounds which are soluble in water, have high melting point and are good conductor of electricity in their aqueous solution or molten state.
– Ores are minerals from which a metal can be profitably extracted.
– Metals are extracted from their ores according to their reactivity.
– Sulphide and chloride ores are roasted while carbonate ores are roasted.
– Pure metals can be obtained using electrolytic refining process.
– Metals are generally attacked by air and corrode. To alter the properties of metals alloys are made.
– Steel, stainless steel, amalgams, brass, bronze and solder are some alloys.

METALS AND NON-METALS

INTRODUCTION
 
All the materials around us are made up of chemical elements, which are found in the earth crust. Earth is the source of coal, petroleum, graphite, diamond and many other minerals of metals and non-metals. We get various useful things like gasoline, kerosene, wax, coal gas and natural gas from the natural resources, which are made up of many non-metals. These elements occur as minerals and rocks in the earth's crust. Some of these elements like oxygen, nitrogen and carbondioxide occur in atmospheric air.
There are more than 115 elements known at present 80% of these elements are metals and rest are non-metals.
On the basis of their properties , all the elements can be divided into two main groups: metals and nonmetals.
 
METALS
 
Metals are the elements that conduct heat and electricity and are malleable and ductile. Some of the examples of metals are : Iron, Aluminium, Copper, Silver, Gold, Platinum, Zinc.
Metals are the elements which form positive ions by losing electrons (or donating electrons). Metals are known as electropositive elements because they can form positive ions by losing electrons. The most abundant metal in the earth’s crust is aluminium.
 
NON-METALS
 
Non-metals are the elements that does notconduct heat and electricity and are neither malleable nor ductile. They are brittle. Some of the examples of non-metals are : Carbon, Sulphur, Phosphorus, Silicon, Hydrogen, Oxygen, Nitrogen. The two allotropic forms of carbon element, diamond and graphite are also non - metal.
 
Non-metals are the elements which form negative ions by gaining electons. Non-metals are known as electronegative elements because they can form negative ions by gaining electrons. Carbon is one of the most important non-metals, as life on this earth is based on carbon compound because the carbon compounds like proteins, fats, carbohydrates, vitamins and enzymes etc. are essential for the growth and development of living organisms.
 
The most abundant non-metal in the earth’s crust is oxygen.
 
 POSITION OF METALS AND NON-METALS IN THE PERIODIC TABLE
 
(i) The elements which are placed on the left hand side (except hydrogen) and in the centre of the periodic table are called metals. Such as sodium, potassium, magnesium, calcium, iron, copper zinc etc.
(ii) The elements which are placed on the right hand side of the periodic table are called non-metals such as oxygen, nitrogen, chlorine, fluorine etc. These metals and non-metals are separated from each other in the periodic table by a zig-zag line. The elements placed in the zig-zag line show some properties of metals and some properties of non-metals are called metalloids. Such as boron(B), silicon(Si), germanium(Ge), arsenic(As), antimony(Sb), tellurium(Te) and polonium(Po).
 
(iii) The position of metals, non-metals and metalloids are shown in a simple form in figure.. Metals present at the extreme left are known as light metals, while those are present in the centre of the periodic table are called heavy metals or transition metals.
 
(iv) The elements at the extreme left of the periodic table are most metallic and those on the right are least metallic or non-metallic.
Thus, metallic character decreases on going from left to right side in the periodic table. For example, sodium is more metallic than aluminium because sodium is on the left hand side of aluminium.
 
(v) However on going down in a group the metallic character increases. For example, carbon is non-metal while lead is metal because metallic character increases down in a group.
CBSE Class 10 Science Metals and Non metals Notes Set A
 
 ELECTRONIC VIEW OF METAL
 
An element is called metal, which forms positive ions (or cations) by losing electron.
Example : Sodium is a metal which forms sodium ion (Na+) by losing one electron.
Similarly, magnesium metal forms Mg2+ by losing two electrons, Al metal forms Al3+ by losing three electrons.
 
Thus, metals are also known as electropositive elements.
 
The atoms of metals have 1 to 3 electrons in their outermost shell. For example, all the alkali metals have one electron in their outermost shell. (Lithium-2, 1, sodium 2, 8, 1, potassium-2, 8, 8, 1, ... etc). Sodium 11(2, 8, 1) magnesium 12 (2, 8, 2) and aluminium 13 (2, 8, 3) are metals having 1, 2 and 3 electrons respectively in their outermost shell, which lose these electron easily. The number of electrons lost by an atom of a metal is called its valency.
 
Thus metals have 1 to 3 electrons in their valence shell of their atoms.
 
Exceptions : Hydrogen and Helium. Hydrogen is a non-metal having 1 electron in its outermost shell of its atom. Helium having 2 electrons in its outermost shell of its atom.
 
PROPERTIES OF METALS
 
 PHYSICAL PROPERTIES OF METALS :
 
1. Metals are malleable, i.e. metals can be beaten into thin sheets with hammer (without breaking)
 
Malleability is an important property of metals. Gold and Silver metals are some of the best malleable metals. Aluminium foils are used for packing food items like biscuits, chocolates, medicines, cigarettes, etc.
 
ACTIVITY - 1
Aim: To test that metals are malleable, i.e. can be hammered into sheets.
 
Method:
 
(i) Take piece of iron, zinc, lead and copper.
 
(ii) Place anyone metal on the block of iron and strike it four or five times with a hammer.
 
(iii) Repeat with other metals.
 
(iv) Record the change in shape of these metals.
 
Discussion and conclusion
 
It is observed that metals can be beaten into thin sheets, Le., they are melleable.
 
2. Metal are ductile, that is, metals can be drawn (or stretched) into thin wires.
 
Ductility is another important property of metals. Gold is the most ductile metal. For example, 1 gram of gold can be drawn into a thin wire about 2 kilometer long. Copper and aluminium metals are also very ductile and can be drawn into thin copper wires and aluminium wires.
 
ACTIVITY - 2
Aim: To justify that metals are ductile, i.e., can be drawn into wire.
 
Method:
 
(i) Consider some metals such as iron, copper, aluminium, lead etc.
 
(ii) Check which of these metals are availabte in the form of wire.
 
Discussion and conclusion
 
As wires of iron, copper and aluminium are easily available, this shows that metals can be drawn into wires i.e., they are ductile.

3. Metals are good conductors of heat.

Metals allow heat to pass through them easily. Take a flat aluminium rod and stick some nails upon the rod with the help of wax. Start heating the free end of the aluminium rod by keeping a burner below it. We will see that the iron nails attached to aluminium rod with wax start falling one by one because heat travels from the left side to the right side along the aluminium rod. It melts the wax which holds the nails. Silver metal is the best conductor of heat. The cooking utensils and water boilers, etc., are usually made up of copper or aluminium metals because they are very good conductors of heat. Heat conductivity is an important property of metals.

ACTIVITY - 3

Aim: To test that metals are good conductors of heat and have high melting point.

Method:

(i) Take an aluminium or copper wire. Clamp the wire on a stand.

(ii) Fix a pin to the free end of the wire using wax.

(iii) Heat the wire with a spirit lamp, candle or a burner near the place where it is clamped.

CBSE Class 10 Science Metals and Non metals Notes Set A

Now answer

(i) What do you observe after some time?

(ii) Does the metal wire melt?

Discussion and conclusion

We observe that on heating the wire near the clamp, after some time the pin falls down. This shows that heat flows through the wire and melts the wax. Further, the wire does not melt even after heating for a long time. This shows that metals have high melting points.

4. Metals are good conductors of electricity

Metals allow electricity (or electric current) to pass through them easily. Silver metal is the best conductor of electricity. The electric wires are made of copper and aluminium metals because they are very good conductors of electricity.

ACTIVITY - 4

Aim: To test that metals are good conductor of electricity.

Method:

(i) Set up an electric circuit as shown in figure.

(iii) Place the metal to be tested in the circuit between terminals A and B as shown in the figure.

Now Answer

Does the bulb glow? What does this indicate ?

Discussion

The bulb glows. This shows that electric current flows through the metal.

Conclusion

Metals are good conductor of electricity.

5. Metals are lustrous (or shiny) and can be polished

Metals are lustrous, they have a shining surface. For example gold, silver and copper are shiny metals and they can be polished. The property of a metal having a shining surface is called ‘metallic lustre’.
The metals lose their shine or brightness by keeping in air for a long time and acquire a dull appearance due to the formation of a thin layer of oxide, carbonate or sulphide on their surface (by the slow action of the various gases present in air).

ACTIVITY - 5

Aim : To check that metals have lustre, i.e., a shining surface.

Method:

(i) Take samples of iron, copper, aluminium and magnesium. Note the appearance of each sample.

(ii) Clean the surface of each sample by rubbing them with sand paper and note their appearance again.

Discussion: The surface of the metals is dull because they are covered with a layer of oxide, hydroxide, carbonate etc. due to the attack of gases present in the air on their surface. On rubbing the surface with sand paper this layer is removed and a shining surface appears.

Conclusion: Metals in the pure state (or freshly prepared or cut) have shining surface.

Q. Why do metals possess lustre?

Explanation

When ligth falls on the surface of a metal, the atoms absorb photons as energy. They get excited and start vibrating. These vibrating electrons release energy in the form of light. Therefore, metal surface shines and metals possess lustre.

6. Metals are generally hard (except sodium and potassium which are soft metals).

Most of the metals like iron, copper, aluminium, etc. are very hard. Some exceptions Sodium and potassium are soft metals which can be easily cut with a knife.

ACTIVITY - 6

Aim: To test that metals are hard and hardness varies from metal to metal.

Method:

(i) Take small piece of iron, copper, aluminium and magnesium. Try to cut these metals with a sharp knife.

(ii) Hold a piece of sodium metal with a pair of tongs.

Caution: Always handle sodium metal with care. Dry it by pressing between the folds of a filter paper. Put it on a watch glass and try to cut it with a knife.

Discussion and conclusion

All the four metals (Fe, Cu, AI and Mg) are found to be cut with difficulty. This shows that metals are hard. The ease of cutting is found to be in the order Mg > Al > Cu > Fe. This shows that hardness varies from metal to metal. Sodium can be cut very easily. Hence sodium is soft, Le., it is an exception.

7. Metals are strong (except sodium and potassium metals which are not strong).
They can hold large weights without snapping (without breaking). For example iron metal (in the form of steel) is very strong. Due to this iron met.

8. Metals are solid at room temperature (except mercury which is a liquid metal).

9. Metals have high melting points and boiling points (except sodium and potassium metals which have low melting and boiling points)
Example, iron metal has a high melting point of 1535°C. Copper metal has also a high melting point of 1083°C. Sodium and potassium metals have low melting points (of 98°C and 64°C respectively).

10. Metals have high densities (except sodium and potassium metals which have low densitites)
The density of iron is 7.8 g/cm3 which is quite high. Sodium and potassium metals have low densities (of 0.97 g/cm3 and 0.86 g/cm3 respectively)

11. Metals are sonorous. That is metals make sound when hit with an object.
The property of metals of being sonorous is called sonorousness or sonority. It is due to the property of sonorousness (or sonority) that metals are used for making bells and strings (wires) of musical instruments like sitar and violin.

12. Metals usually have a silver or grey colour (except copper and gold) 
cbse-class-10-science-metals-and-non-metals-notes-set-b

♦ USES OF SOME METALS

(i) Many metals and their compounds are useful in our daily life. These are as follows : Aluminium is used to prepare utensils and house hold equipments like vacuum cleaner. Aluminium is extensively used in making bodies of rail, cars, automobiles, trucks and aircraft. Aluminium wires are widely used in electrical work. Aluminium foil is used to wrap chocolate cigarette and medicines and to seal milk bottles.
(ii) Major use of copper is in making electrical wires & cables. Copper is also used in making utensils, steam pipes, coin and in electroplating.
(iii) Steel is an alloy of iron which is used for making parts of machines, as building material and in the construction of refrigerator. As a matter of fact steel is said to be the back bone of industry.
(iv) Gold and silver called noble metals (or coinage metals) are used in jewellery.
(v) Mercury is used in thermometers barometers and to prepare amalgams.
(vi) Platinum is used to make crucibles and electrodes.
(vii) Zinc is used to galvanize iron, to prepare roofing material, container of dry cells and to make brass when mixed with copper.
(viii) Metal like sodium, titanium and zirconium find their applications in atomic energy, research and medical industry.
(ix) Titanium (Ti) and its alloys are used in aerospace, marine equipments, aircraft frames, chemical industries and chemical reactors. The wide application of titanium is attributed to its resistance to corrosion, high melting points and high strength.

♦ CHEMICAL PROPERTIES OF METALS :

1. Reaction of Metals with oxygen (Air)
When metals are burnt in air, they react with the oxygen of air to form metal oxides :
Metal + Oxygen → Metal oxide
 From air            (Basic oxide)
Metals react with oxygen to form metal oxides. Metal oxides are basic in nature. The vigour of reaction with oxygen depends on the chemical reactivity of metal.
(i) Sodium metal reacts with the oxygen at room temperature to form a basic oxide called sodium oxide:
4Na(s)  +  O2(g) → 2Na2O(s)
sodium   oxygen     sodium oxide
(Metal)  (from air) (Basic oxide)
Potassium metal and sodium metal are stored under kerosene oil to prevent their reaction wilh the oxygen, moisture and carbon dioxide. Some of the metal oxides dissolve in water to form alkalies.
Eg. Na2O(s)    +    H2O(l)   →   2NaOH(aq)
    sodium oxide water sodium hydroxide
    (basic oxide)  (An alkali)
(ii) Magnesium metal does notreact with oxygen at room temperature. But on heating, magnesium metal burns in air giving instense heat and light to form a basic oxide called magnesium oxide (which is a white powder)
2Mg(s)   +   O2(g)    2MgO(s)
Magnesium Oxygen     Magnesium oxide
(Metal)    (From air)    (Basic oxide)
Magnesium oxide dissolves in water partially to form magnesium hydroxide solution :
MgO(s)   +    H2O(l)     →   Mg (OH)2(aq)
Magnesium oxide water    Magnesium hydroxide
(iii) Aluminium metal burns in air on heating to form aluminium oxide :
4Al      +      3O2     →    3Al2O3 (s)
Aluminium  Oxygen    Aluminium oxide
(Metal)     (From air)   (Amphoteric oxide)
Those metal oxides which show basic as well as acidic behaviour are known as amphoteric oxides. Aluminium metal and zinc metal form amphoteric oxides. Amphoteric oxides react with both, acids as well as bases to form salts and water. Example :
(a) Al2O3(s)     +    6HCl    →     2AlCl3(aq)     +    3H2O(l)
Aluminium oxide  Hydrochloric  acid Aluminium  chloride Water
   (Base)                (Acid)                (Salt)
(b) Al2O3(s)   +   2NaOH     →        2NaAlO2(aq)       +   H2O(l)
Aluminium oxide Sodium hydroxide Sodium aluminiate   Water
       (Acid)             (Base)                     (Salt)
(iv) Zinc metal burns in air only on strong heating to form zinc oxide :
2 Zn(s)    +   O2(g)   →   2 ZnO(aq)
Zinc             Oxygen Zinc      oxide
(Acid)                             (Amphoteric oxide)
Zinc oxide reacts with hydrochloric acid to form zinc chloride (salt) and water.
ZnO(s)    +    2HCl(aq)        →     ZnCl2(aq)   +    H2O(I)
Zinc oxide     Hydrochloric acid   Zinc chloride        Water
(Base)              (Acid)                      (Salt)
(v*) Iron metal does notburn in air even on strong heating. Iron reacts with the oxygen on heating to form iron (II, III) oxide :
3Fe(s)     +     2O2(g)     →    Fe3O4(s)
Iron           Oxygen Iron     (II, III) oxide
(vi*) Copper metal also does notburn in air even on strong heating. Copper reacts with the oxygen on prolonged heating to form a black substance copper (II) oxide :
2Cu (s)    +    O   →   2CuO (s) 
Copper       Oxygen    Copper (II) oxide

♦ NATURE OF METALLIC OXIDE
Generally, metallic oxides are basic in nature except aluminium and zinc oxides which are amphoteric in nature. This means these oxides (Al2O3, ZnO) react with base as well as acid. The basic oxide of metals react with acid to give salt.
For example :
cbse-class-10-science-metals-and-non-metals-notes-set-b

2. Reaction of Metals with water
Metals react with water to form a metal hydroxide (or metal oxide) and hydrogen gas.
(i) Potassium react violently with cold water to form potassium hydroxide and hydrogen gas : 
cbse-class-10-science-metals-and-non-metals-notes-set-b

cbse-class-10-science-metals-and-non-metals-notes-set-b

ACTIVITY - 7

Aim: To study the reactivity of metals with water.
Caution: This activity needs teacher’s assistance.
Method:
(i) Collect the samples of sodium, potassium, calcium, magnesium, zinc and copper.
(ii) Put small piece of the samples separately in beakers half-filled with cold water.
(iii) Put the metals that do not react with cold water in beaker half-filled with hot water.
(iv) For the metals that do not react with hot water, arrange the apparatus (to produce steam) and observe their reaction with steam.  
cbse-class-10-science-metals-and-non-metals-notes-set-b

Now Answer
(i) Which metals reacted with cold water? Arrange them in increasing order of their reactivity with cold water.
(ii) Does any metal produce fire on water ?
(iii) Does any metal start floating after some time ?
(iv)Which metals did not react even with steam ?

Discussion
(i) Na and K metals react vigorously with cold water to form NaOH and H2 gas is liberated. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(vii) Copper do not react with water even under strong conditions. The above reactions indicate that sodium and potassium are the most reactive metals while copper is less reactive.

Conclusion
The reactivity order of these metals with water are
K > Na > Ca > Mg > Al > Zn > Fe > Cu

3. Reaction of metals with Dilute Acids :
Metals usually displace hydrogen from dilute acids. When a metal reacts with a dilute acid, then a metal salt and hydrogen gas are formed
Metal + Dilute acid → Metal salt + Hydrogen
(i) Sodium metal reacts violently with dilute hydrochloric acid to form sodium chloride and hydrogen:
2Na(s)     +     2HCl(aq)    →    2NaCl(aq)    +    H2(g)
Sodium        Hydrochloric   Sodium chloride     Hydrogen
(ii) Magnesium reacts quite rapidly with dilute hydrochloric acid forming magnesium chloride and hydrogen gas :
Mg(s)    +    2HCl(aq)      →      MgCl2(aq)       +        H2(g)
Magnesium   Hydrochloric acid  Magnesium chloride   Hydrogen
(iii) Aluminium metal at first reacts slowly with dilute hydrochloric acid due to the presence of a tough protective layer of aluminium oxide on its surface.But when the thin, outer oxide layer gets dissolved in acid.
Aluminium metal reacts rapidly with dilute hydrochloric acid to form aluminium chloride and hydrogen gas :
2AI(s)     +    6HCI(aq)      →      2AlCl3(aq)      +      3H2(g)
Aluminium    Hydrochloric acid    Aluminium chloride  Hydrogen
The reaction of aluminium with dilute hydrochloric acid is less rapid than that of magnesium, so aluminium is less reactive than magnesium.
(iv) Zinc reacts with dilute hydrochloric acid to give zinc chloride and hydrogen gas(but the reaction is less rapid than that of aluminium)
Zn(s)      +     2HCl(aq)     →     ZnCl2(aq)     +    H2(g)
Zinc       Hydrochloric acid        Zinc chloride       Hydrogen
This reaction shows that zinc is less reactive than aluminium.
(v) Iron reacts slowly with cold dilute hydrochloric acid to give iron (II) chloride and hydrogen gas:
Fe(s)    +    2HCl(aq)    →     FeCl2      +          H2(g)
Iron       Hydrochloric acid   Iron (II) chloride  Hydrogen
(vi) Copper does notreact with dilute hydrochloric acid (or dilute sulphric acid) at all. This shows that copper is even less reactive than iron :
Cu (s)    +     HCl (aq)     →     No reaction
Copper      Hydrochloric acid
Metals like copper and silver which are less reactive than hydrogen, does notdisplace hydrogen from dilute acids.

♦ REACTION OF METALS WITH SOLUTIONS OF OTHER METAL SALTS

When a more reactive metal is placed in a salt solution of less reactive metal, then the more reactive metal displaces the less reactive metal from its salt solution . This reaction is also known as displacement reaction. Let us learn it with the help of following activity.

ACTIVITY - 8

Aim : To compare the reactivity of the metals.
Procedure : Take a clean wire of copper and an iron nail and two test tube. Now dissolve copper sulphate in water in one test tube and ferrous sulphate in another test tube. Place iron nail in the blue coloured copper sulphate solution with the help of a thread and copper wire in the greenish colour ferrous sulphate solution as shown in figure as below. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

Observation : The blue colour of copper sulphate has faded and becomes greenish. The green colour of the solution is due to the formation of iron (II) sulphate and copper is displaced. A reddish-brown coating is formed on the surface of iron nail. The reaction is represented by the chemical equation.
Fe(s)   +   CuSO4(aq)     →          FeSO4(aq)    +    Cu(s)
Iron    Copper sulphate solution  Ferrous sulphate
But the greenish colour of FeSO4 does notchange. That means no reaction take place.
Conclusion : These activities shows that iron metal is more reactive than copper.
Similarly,

♦ REACTION OF COPPER WITH SILVER NITRATE SOLUTION :

When a strip of copper metal is placed in a solution of AgNO3. The solution becomes gradually blue and a shining coating of silver metal gets deposited on the copper strip. The reaction may be written as :
2AgNO3(aq)       +     Cu(s)     →     Cu(NO3)   +   2
Silver nitrate                                  Copper nitrate   Silver
(colourless solution)                         (blue colour)
However, if we place silver wire in a copper sulphate solution no reaction occurs. This means copper can displace silver from its salt solution but silver cannot displace copper from its solution. i.e. copper is more reactive metal than silver.

PROPERTIES OF NON-METALS

♦ NON-METALS AND THEIR GENERAL PROPERTIES
Non-metals are present on the right hand side of the periodic table (exception : Hydrogen). Among the total known elements, there are only 22 non-metals, out of which 11 are gases like oxygen, nitrogen, hydrogen one is a liquid (Bromine) and the rest 10 are solids such as sulphur, phosphorus and the allotrops of carbon (Diamond and graphite).

♦ ELECTRONIC VIEW OF NON-METALS
An elements is called non-metal which form ions by gaining electrons. For example, oxygen is a nonmetal which form O2– ions by gaining two electrons. Similarly, nitrogen form N3– ions by gaining three electrons.
Thus, non-metals also known as electronegative elements.
The atoms of non-metals have usually 4 to 8 electrons in their outer most shell. For example, Carbon (At No. 6), Nitrogen (At. No. 7), Oxygen (At. No. 8), Fluorine (At. No. 9) and Neon (At. No. 10), have respectively 4, 5, 6, 7 and 8 electrons in their outermost shell. However, there are two exceptions namely hydrogen and helium which have one and two electrons in their valence shell or outer most shell, but they are non-metals. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

♦ PHYSICAL PROPERTIES OF NON-METALS

1. Non-metals are neither malleable nor ductile. Non-metals are brittle (break easily).
Solid non-metals can neither be hammered into thin sheets nor drawn into thin wires. For example, sulphur and phosphorus are solid non-metals which are non-malleable and non-ductile. The property of being brittle (breaking easily) is called brittleness. Brittleness is an important property of non-metals.

2. Non-metals does not conduct heat and electricity.
Non-metals does notconduct heat and electricity because unlike metals, they have no free electrons (which are necessary to conduct heat and electricity). For example, sulphur and phosphorus are nonmetals which does notconduct heat and electricity. There is, however one exception, carbon (in the form of graphite) is the only non-metal which is a good conductor of electricity because of it’s structure.

3. Non-metals are not lustrous (not shiny). They are dull.
Non-metals does nothave a shining surface. For example, sulphur and phosphorus are non-metals which have non lustre. Iodine is a non-metal having lustrous appearance.

4. Non-metals are generally soft (except diamond which is extremely hard non-metal)

5. Non-metals are not strong. They are easily broken.

6. Non-metals may be solid, liquid or gases at the room temperature.

7. Non-metals have comparatively low melting points and boiling points (except diamond which is a non-metal having a high melting point and boiling point).
The melting point of sulphur is 115°C which is quite low. The melting point of diamond is, however more than 3500°C which is very high.

8. Non-metals have low densities, that is, non-metals are light substances.
The density of sulphur of 2g/cm3.

9. Non-metals are non-sonorous. They does not produce sound when hit with an object.

10. Non-metals have many different colours.
On the basis of the above discussion of the physical properties of metals and non-metals, we have concluded that elements can not be grouped according to the physical properties alone, as there are many exceptions.

For example,

(i) All metals except mercury are solids at room temperature. We know that metals have very high melting points but gallium (Ga) and caesium (Cs) have very low melting points. These two metals will melt if we keep them at our palm.
(ii) Iodine is a non-metal but it is lustrous.
(iii) Alkali metals such as Lithium, Sodium and Potassium are soft and they can be easily cut with a knife.
i.e. they have very low densities and low melting points.
(iv) Carbon is a non-metal that can exist in different forms. Each form is called an allotrope of Diamond, an allotrope of carbon is the hardest natural substance. which has very high melting and boiling point.
Graphite is another allotrope of carbon which is good conductor of electricity.
The elements can be more clearly classified as metals and non-metals on the basis of their chemical properties. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

cbse-class-10-science-metals-and-non-metals-notes-set-b

cbse-class-10-science-metals-and-non-metals-notes-set-b

THE REACTIVITY SERIES

The arrangement of metals in order of decreasing reactivities is called reactivity series or activity series of metals. After performing displacement experiments the following series has been developed. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

♦ CHARACTERISTICS OF REACTIVITY SERIES:

(i) The most reactive metal is placed at the top and the least reactive metal is placed at the bottom of the table.
(ii) Metals present above the hydrogen in reactivity series can displace hydrogen from dilute acids.
(iii) A metal can displace the metals placed below it in the reactivity series.
(iv) Metals present at the top are more elecro-positive, so they will occur in combined or compound form only in nature.
(v) Metals at the bottom are less reactive and do not react easily so they may be present in free state in nature.

Ex.1 A, B and C are three elements which undergo chmical change according to the following equations :
A2O3 + 2B — B2O3 + 2A
3CSO4 + 2B — B2(SO4)3 + 3C
3CO + 2A — A2O3 + 3C
Write the anme of the most reactive and the least reactive elements.
Sol. (i) In the first reaction, B displaces A, so B is more reactive than A.
(ii) In second reaction, B displaces C, so B is more reactive than C.
(iii) In third reaction, A displaces C, so A is more reactive than C.
So, B is more reactive than A and C and A is more reactive than C, So the order of their reactivities is as follows:
B > A > C

Ex.2 Explain why zinc metal can displace copper from copper sulphate solution but copper cannot displace zinc from zinc sulphate solution.
Or
When a piece of copper metal is added to a solution of zinc sulphate, no change takes place, but the blue colour of copper sulphate fades away when a piece of zinc is placed in its solution.
Sol. When a piece of zinc is placed in a solution of copper sulphate, zinc being more reactive than copper, can displace copper from its salt solution and forms zinc sulphate and blue colour of copper sulphate fades away slowly, but when a piece of copper sulphate fades away slowly, but when a piece of copper metal is added to a solution of zinc sulphate, no change takes place as copper being less reactive than zinc, cannot displace zinc from zinc sulphate.
cbse-class-10-science-metals-and-non-metals-notes-set-b

HOW ARE METAL AND NON METAL REACT?

It is clear from the above table that except helium, all other noble gases have 8 electrons (octet) in their outermost shell. Which represent a highly stable electronic configuration. Due to this stable configuration, the noble gases have no any tendency to lose or gain electrons. So they exist monoatomic, sodium atom has one electron in its outermost shell. If it loses the electon from its M shell the its L shell becomes the outermost shell. which has stable octet like noble gases. The nucleus of this atom still has 11 protons but the number of electrons has 10. Therefore, if becomes positively charged sodium ion or cation (Na+).
cbse-class-10-science-metals-and-non-metals-notes-set-b

On the other hand chlorine has seven electrons in its outer most shell and it require one more electron to complete its octet. The nucleus of chlorine atom has 17 protons and the number of electrons become 18. This makes chloride ion, Cl as negatively charged 
cbse-class-10-science-metals-and-non-metals-notes-set-b

So, Na+ and Cl ions being oppositely charged atoms which attract each other and are held by strong electrostatic forces of attraction to exist as NaCl. In other words, Na+ and Cl ions are held together by electrovalent or ionic bond.
cbse-class-10-science-metals-and-non-metals-notes-set-b

The formation of one more ionic compound magnesium chloride :
The electronic configuration of magnesium (Mg) and chlorine atoms are :
Mg12 : 2, 8, 7
Cl17 : 2, 8, 7
Magnesium atom has two electrons in its valence shell. It has a tendency to lose both of its electrons to attain the nearest noble gas configuration (i.e. Ne). Mg → Mg2+.
On the other hand, chlorine has only one electron less than the nearest noble gas (i.e. Ar) configuration.
The magnesium loses its both the valence electrons to two chlorine atoms, each of which is need of one electron to form Cl ion. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

The compounds formed by the transfer of electrons from a metal to a non-metal are known as ionic compound or electrovalent compounds. The structure of some common ionic compounds are given below :

Structure of some common ionic compounds :
cbse-class-10-science-metals-and-non-metals-notes-set-b

ACTIVITY - 9

Aim: To study the properties of ionic compounds.
Method:
(i) Take samples of sodium chloride, potassium iodide, barium chloride or any other salt from the science laboratory.
(ii) Take a small amount of sample on a metal spatula and heat directly on the flame. Repeat with other samples.
(iii) Try to dissolve the compound in water and kerosene.
(iv) Make a circuit as shown in figure and insert the electrooes into a solution of one salt. Test the other salt samples too in this manner.
Now Answer
(i) What is the physical state of the salt taken ?
(ii) Did the samples impart any colour to the flame on heating ?
(iii) Did the compounds melt on heating?
(iv) Are the compounds soluble in water or kerosene ?
(v) Did the electric bulb glows on passing electric current ?
(vi) What is your inference about the nature of these compounds?
Discussion
(i) All the salts taken are solids. Each salt imparted a particular colour to the flame.
(ii) The compounds did not melt on heating.
(iii) The compounds were soluble in water but not in kerosene.
(iv) The electric bulb glows on passing electric current. All these properties show that the compounds are ionic in nature.
Conclusion
(i) Ionic compounds are generally solids.
(ii) They impart a characteristic colour to the flame.
(iii) They are soiuble in a polar solvent like water and insoluble in non-polar solvent like kerosene, petrol, etc.
(iv) Their molten or aqueous solution conduct electricity.

♦ Following are the general properties of ionic compounds.
(a) Physical state
Ionic compounds are solids and relatively hard because of the strong force of attraction between the positive and negative ions. This force of attraction is also known as strong electrostatic force of attraction. These compounds are generally brittle and break into pieces when pressure is applied.
(b) Solubility
Electrovalent compounds are generally soluble in water (because of their polar nature) and insoluble in solvents such as kerosene, petrol, etc.
(c) Melting and boiling points
Ionic compounds have high melting and boiling points, due to the strong electrostatic force of attraction belween the oppositely charged ions. Therefore, large amount of energy is needed to break these bonds.
(d) Conduction of electricity
Ionic compounds in the solid state do not conduct electricity because movement of ions in the solid state is not possible due to their rigid structure. But they can conduct electricity in molten or aqueous state.
(e) Colour to the flame
Most of the salts when brought into the flame, impart characteristic colour to the flame. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

IMPORTANT INFORMATION

Hydrogen gas is not evolved when metals such as Zn, Fe, Cu and Al reacts with nitric acid. Because HNO3 is strong oxidising agent. It oxidises H2 gas to water and itself gets reduced to form oxides of (NO, N2O and NO2) nitrogen. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

♦ AQUA REGIA (ROYAL WATER)
Aqua regia is a Latin word it means " royal water". It is a freshly prepared mixture of concentrated hydrochloric acid and concentrated nitric acid in the ratio of 3 : 1. It is a highly corrosive, fuming liquid and it is used to dissolve gold and platinium.

OCCURENCE OF METALS

The main source of metal is earth’s crust. Some metals also occur in sea water. The metals are found in nature in :
(1) Native state (or free state) : Only a few less reactive metals like silver, gold platinum etc., are found in the free state in which they are called “native metals”.
(2) Combine state : i.e., in the from of their compounds admixed invariably with various useless impurities such as clay, sand, rocky material, etc. Usually, metals are found in the form of oxides, sulphides, carbonates, phosphates, halides silicates, etc.
(i) The naturally occurring form of metal in combined state, is known as “mineral”.
(ii) Those naturally occurring minerals, which are economically suitable for commercial extraction of metals, are known as ‘ores’. Thus, every ore is a mineral, but every mineral is not an ore.
(iii) The rocky and earthy impurities (like clay, sand) generally associated with ore, are called gangue (or matrix). 
cbse-class-10-science-metals-and-non-metals-notes-set-b

Note :
(1) Sodium a very reactive metal, and reacts readily with moisture, oxygen and carbon dioxide of air.
So sodium cannot exit ‘free’ in nature. Hence, it is not found ‘native’ in nature.
(2) Sodium is highly reactive metal, and has affinity for oxygen. If it is exposed to air, a coating of the oxide is formed and sometimes, it may even catch fire. Consequently, sodium metal should not be exposed to air. Hence, sodium is stored under kerosene.
(3) Aluminium is a reactive metal, so it is not found in free state in nature. It occurs in the form of its compounds, chief of which is bauxite (Al2O3 2H2O).
(4) Gold and silver occupr low position in the activity series. Consequently, they are least reactive elements and are not effected by most chemicals, atmospheric oxygen, moisture, carbon dioxide etc. Hence, they often occur in free or native state in nature.

Extraction of metals : We have learnt about the reactivity series of metals, according to which, the metals at the “bottom” of the reactivity series are the “least reactive” and these are often found in a free-state, e.g., Au, Ag, Pb and Cu. However Cu and Ag are also found in combined state as their oxides and sulphides. On the other hand, metals at the “top” of the reactivity series are so reactive, they are never found in nature as free elements, e.g., Li, K, Na, Ca, Mg etc. The metals in the “middle” of the reactivity series (e.g., Al, Zn, Fe, Pb etc.) are moderately reactive and they are found in the earth’s crust mainly as oxides, sulphides or carbonates [e.g., Al2O3. 2H2O (bauxite), HgS (cinnaber), ZnCO3 (calamine)].
On the basis of reactivity seires, we can have following three groups of elements :
(i) Metals of low reactivity.
(ii) Metals of medium rectivity.
(iii) Metals of high reactivity.

Metallurgy : is the process of extracting a metal in the free form from its ore and then refining it for use.
Various steps involved in the extraction of metals from their ores are generally as follows:
(a) Concentration (or enrichment) of ore
(b) Conversion of concentrated ore into oxide
(c) Reduction of oxide ore into impure metal
(d) Refining of impure metal.

(a) Con centration (or enrichment) of ore : The ore is, generally, associated with useless rocky and earthy impurities (like clay, sand etc.), called ‘gangue’ or matrix. The ‘concentration’ (or enrichments) of ore means removal of gangue from the powdered ore. Thus, the percentage of the metal in the concentrated ore is higher than that in the original ore. The concentration of ore can be brought about in the following ways. depending upon the type of ore such as hydraulic washing, froth floatation method, magnetic separation etc.

(i) Levigation or gravity separation or hydraulic washing
This method is based upon the difference in the densities of the ore particles and impurities (gangue). Example: Haemetite ore of iron. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(ii) Froth floatation
This method is based on the difference in the wetting properties of the ore and gangue particles with water and oil. It is used for enrichment of sulphide ores. Example: ZnS, HgS. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(iii) Liquation
This method is based on difference in melting point of ore and gangue particles. Example: ore of tin and zinc.

(iv) Magnetic separation
This method is based on difference in the magnetic properties of the ore and gangue. Example:
magnetite (Fe3O4) ore of iron. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(v) Chemical separation
When none of the physical propertry makes the difference, then we use chemical properties as the basis for enrichment. e.g. Bayer’s process for alumina enrichment.

Next steps of metallurgy depend on the type of metal to be extracted :
(a) Extracting metals low in reactivity series : Since these metals are unreactive, so the oxides of these metals can be “reduced” by heating alone. For example, cinnabar (HgS) an ore of mercury changes to mercury on heating 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(b) Extracting metals in the middle of the reactivity series : Since these metals (e.g. Fe, Zn, Pb, Cu, etc.) are moderately reactive, so they are usually found in earth’s crust as sulphides or carbonates.
Consequently are converted into metal oxides.
(i) The process of conversion of metal sulphide to oxide by strongly heating in the presence of excess air, is called roasting. For example : 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(ii) The proces of conversion of metal carbonate to oxide by heating strongly in limited air, is called calcination. For example : 
cbse-class-10-science-metals-and-non-metals-notes-set-b

Reduction of oxide to metal : The metal oxides obtained above are reduced by hearting with suitable reducing agents like carbon. For example : 
cbse-class-10-science-metals-and-non-metals-notes-set-b

It may be pointed out here that besides using carbon (coke), to reduce metal oxides to metals, sometimes, displacement reactions are also employed. The highly reactive metals (e.g., Na, Ca, Al, etc.) are employed as reducing agents, since they displace metals of lower reactivity from their compounds, For example :
2MnO2(s) + 4Al(s) —→ 3Mn(l) + 2Al2O3(s) + Heat
Such a displacement reaction is highly exothermic (i.e., lot of heat is evolved), so the metal produced is in molten state [e.g., Mn(l)] Al is also used to reduce iron (III) oxide (Fe2O3) and this reaction is called thermite reaction and used to join railway trackes or machine parts.
Fe2O3(s) + 2Al(s) —→ 2Fe(s) + Al2O3(s) + Heat

Difference between Roasting and Calcination 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(c) Extracting metals near the top of the reactivity series : Since these metals are highly reactive, so their oxides cannot be reduced by heating with carbon. For example, Na2O(s), MgO(s), CaO(s), Al2O3(s), etc. cannot be reduced by heating with carbon. This is because these metals possess more affinity for oxygen than carbon. Consequently, these metals are extracted by electrolytic reduction process. For example, when molten sodium chloride is electrolyed sodium is obtained at the cathode (the negatively charged electrode) : while chlorine is liberated at the anode (the positively charged electrode).
Thus : At cathode : Na+ + e —→ Na(s)
At anode : 2Cl → Cl2 + 2e
Likewise, Al is obtained by the electrolytic reduction of Al2O3.
(d) Refining of metals : the process of purifying the crude metal to get pure metal, is called refining.
The method of metal refining depends on :
(i) the nature of the metal to be purified and (ii) the type of impurities present.
Electrolytic refining : Most of the metals are refined by this method. In this process, a large block of impure metal is made the anode in an electrolytic cell, and a thin sheet of pure metal is made the cathode. Suitable metal salt solution is made as an electrolyte. On passing electric current, pure metal deposits on the cathode sheet; while some of impurities are left in solution, and other noble metal impurities settle below the anode as ‘anode mud’.
For exmple, during the electrolytic refining of a copper, a thick block of impure copper is made anode, and thin plate of pure copper is made cathode. Copper sulphate solution. is used as an electrolyte.
On passing electric current, following reactions take place :
(1) Cu2+ ions (from copper sulphate solution) go to the cathode (negative electrode), where they are reduced to copper, which gets deposited on the cathode. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

Thus, the net result is transfer of pure copper from anode to the cathode. Impurities like zinc, iron etc., go into solution; while noble impurities like silver, gold etc., are left behind as  anode mud.
cbse-class-10-science-metals-and-non-metals-notes-set-b

CORROSION

Any process of deterioration (or destruction) and consequent loss of a solid metallic material, through an unwanted (or unintentional) attack by its environment, starting at its surface, is called corrosion.
Thus, corrosion is a proces “reverse of extraction of metals”.
The most familiar example of corrosion is rusting of iron, when exposed to the atmospheric conditions.
During this, a layer of reddish scale and powder of oxide (Fe2O3 . x H3O) is formed and the iron becomes weak. Another common example is formation of green films of basic copper, when exposed to moist-air containing carbon dioxide. Similarly, silver article turns black after some time, when exposed to air. This is due to the reaction of Ag with H2S present in air to form black coloured Ag2S.
Note :
(i) It may be pointed out that noble metals such as gold and platinum do not corrode easily.
(ii) The process of corrosion is continuous and causes decrease in strength of the metal.

Prevention of rusting :

(i) By painting: The corrosion of a metal can be prevented simply by painting the metal surface by grease or varnish taht forms a protective layer on the surface of the metal which protect the metal from moisture and air.
(ii) Self prevention: Some metals form protective layers.
For example: When zinc is left exposed to the atmosphere, it combines with the oxygen of air to form a layer of zinc oxide over its surface. The oxides layer does not allow iar to go inside the metal. Thus, zinc is protected from corrosion by its own protective layer.
Similarly, aluminium combines with oxygen to form a dull layer of aluminium oxide on its surface which protect the aluminium from further corrosion.

(iii) Cathodic protection: In this method the more reactive metal which is more corrosion-prone is connected to a bar of another metal which is less reactive and to be protected. In this process electron flow from the more reactive metal to the less reactive metal. The metal to be protected becomes the cathode and the mroe reactive metal becomes the anode.
In this way, the two metals form an electrochemical cell and oxidation of the metal is prevented.
Example: The pipelines (iron) under the surface of the earth are protected from corrosion by connecting them to a more reactive metal (magnesium or Zn) which buried in the earth and connected to the pipelines by a wire. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

(vi) Oiling and greasing: Both protect the surface of metal against moisture and chemicals etc. In addition the oil and grease prevent the surface from getting scratched.

(v) Electroplating: It is a very common and effective method to check corrosion. The surface of metal is coated with chromium, nickel or aluminium etc. by electrolysis also called electroplating.
They are quite resistant to the attack by both air and water and check corrosion. If the surface of metal is electroplated by zinc, it is known as galvanisation and in case tin metal is used, then the process is called tinning.

(vi) By alloying: It is a very good method of improving the properties of a metal.

For example: Iron is the most widely used metal. But it is never used in its pure state. This is because pure iron is very soft and stretcheds easily when hot. But, it it is mixed with a small amount of carbon (about 0.05%) it becomes hard and strong.

When iron is mixed with nickel and chromium to form stainless steel which is hard and does not rust, i.e. its properties change. In fact, the properties of any metal can be changed, if it is mixed with some other subtances.

Importance of corrosion : Sometimes corrosion of a metal prevents further corrosion of the underlying metal : For example, when Al is exposed to air a thin coating of Al2O3 on the metal article is formed.
This film, quite adhering and non-porous, thereby it protect the Al metal underneath from further corrosion and damage. This is the reason why Al, being a very reactive metal, is used for making uternsils. 
cbse-class-10-science-metals-and-non-metals-notes-set-b

ALLOYING

“An alloy is a homogeneous solid solution of one metal with one or more metals or non-metals.” such as brass, bronze, steel etc.
Purposes of alloy making : Alloys are generally, made to serve one or more of the following purposes:
(i) To modify chemical activity such as increased resistance to corrosion.
(ii) To harden a metal e.g., copper in gold ornaments.
(iii) To increase the strength and toughness.
(iv) To lower the melting point.
(v) To produce good castings.
For instance, pure iron is very soft and stretches easily, but it is mixed with some metals and nonmetals, the alloys formed show considerable improvement in the qualities.
(i) Steel : When iron has carbon (0.05 to 0.5%) it is called steel. It is hard and strong. It is used for making ships, vehicles and building.
(ii) Stainless Steel : When steel is mixed with nicked and chromium, it is called stainless steel. It is hard and rust-proof. It is used for making utensils, equipments for feed and dairy industry.

Some common Alloys

(i) Brass : It is an alloy of copper and zinc (Cu-60 to 90%; Zn-10 to 40%). It is a yellow coloured alloy and used for making utensils, coins and decorative pieces.
(ii) Bronze : It is an alloy of copper and tin (Cu-88 to 96%; tin-4 to 12%). It is shining light, yellowish coloured alloy. It is used for making statures, ships and medals.
(iii) Solder : It is an alloy of lead and tin (lead 33%; tin 67%). Its melting point is low. It is used for soldering electrical wires.
(iv) Alloying of gold : The purity of gold is expressed in ‘carat’ and 24 carat gold is supposed to be 100% pure. Pure gold or 24 carat gold tis very soft and cannot be sued for making ornaments.
To make is hard, it is alloyed with silver, copper or both. Mosdy 22 carat or 20 carat gold is used for making ornaments. 22 carat gold means 22 parts of pure gold mixed with 2 parts of silver or copper or both.
(v) Duralumin: It is an alloy of aluminium. It contains 95% of aluminium, 4% of copper, magnesium is 0.5% and 0.5% of manganese. It is stronger and lighter than aluminium. Duralumin is used for making bodies of air crafts, helicopters, jets, kitchen ware like pressure cooker. It is also used for making bodies of ships (due to its resistance to sea water corrosion). It is also known as duralium.
(vi) Amalgam: It is an alloy of mercury and one or more other metals is known as an amalagam. It may be solid or liquid. A solution of sodium metal in liquid mercury metal is called sodium amalgam, which is used as a reducing agent. Amalgam of silver, tin and zinc is used by dentists for filling in teeth.

 

 

METALS AND NON METALS
INTRODUCTION
 
Lavoiser classified all elements into metals, nonmetals and metalloids on the basis of their properties.
 
Some commonly used metals, nonmetals and metalloids are given below.
 
 Metals : Iron, Copper, Gold, Silver, Aluminium, Zinc Lead are some commonly used meats.
 
 Nonmetals : Hydrogen, Oxygen, Nitrogen, Carbon, Sulphur, Phosphorus, Chlorine, Bromine, Iodine are commonly used nonmetals.
 
 Metalloids : Boron, Silicon, Arsenic and Germanium are some metalloids.
 
CHARACTERISTICS OF METALS
 
Some important characteristics of metals are :
 
 Metals are good conductors of heat and electricity.
 
 All metals except mercury are solid at room temperature. Mercury is the only metal which is liquid at room temperature.
 
 Metals are malleable and ductile – that is metals can be beaten into thin leaves and drawn into thin wires.
 
 Metals have lustre and can be polished.
 
 Metals have tensile strength.
 
 Metals are electropositive elements. That is, metals have a tendency to lose electrons and form positively charged ions, (called cations).
 
Occurrence of Metals
 
Metals occur in nature in the free as well as in the combined states.
CBSE Class 10 Science Metals and Non metals Notes Set B
 
 All metals which are not affected by water and by the gases present in the air occur in free state in nature.
 
 The naturally-occurring compounds of metals mixed with earthly materials are called minerals.
 
 A mineral from which a metal can be extracted on the commercial scale, economically and easily, is called an ore.
 
PHYSICAL PROPERTIES OF METALS
 
All metals show similar physical properties. There are however a few exceptions.
 
 Physical State : Under normal pressure, all metals except mercury are solids at room temperature. Mercury is liquid at room temperature.
 
 Colour : Most metals except gold and copper are silver-grey in colour. Copper is reddish-brown and gold is golden yellow.
 
 Appearance : All metals are shiny. The characteristic shine of metals is called metallic lustre. Thus all metals have metallic lustre. Metals can be easily polished.
 
 Hardness : Most metals are hard except sodium and potassium. Sodium and potassium metals can be easily cut with a knife. Osmium is hard enough to scratch glass.
 
 Tensile strength : Metals have high tensile strength. Metals are very strong. For example, iron can bear a lot of stress. That is why it is widely used in construction of buildings, bridges, railway lines etc.
 
Malleability : Metals are malleable. This means that metals can be hammered into very thin sheets. Silver can be beaten to very thin leaves. You must have seen silver varak on burfee. Aluminium foil is used in the packaging of food materials.
 
Ductility : Metals are ductile. This means that metals can be drawn into thin wires. Silver and gold can be drawn into very thin wires.
 
Conductivity : Metals are good conductor of heat and electricity. Silver is the best conductor of electricity. Copper is the next best conductor of electricity.
 
Density : Metals, except sodium and potassium have high densities. Sodium and potassium have much lower densities.
 
Sound : Metals are sonorous. Metals when hit by a hammer produce a ringing sound. That is why metal are used for making bells and wires for musical instruments.
 
CHEMICAL PROPERTIES OF METALS
 
All metals give similar chemical reactions. However, the reactivity of a metal depends upon its nature and reaction conditions.
 
Some typical reactions of metals are described below :
 
  Reaction with oxygen : All metals combine with oxygen to form metal oxides. Different metals react with oxygen under different conditions.
CBSE Class 10 Science Metals and Non metals Notes Set B
CBSE Class 10 Science Metals and Non metals Notes Set B

Uses of some Common Metals

Main uses of some common metals are listed below :

CBSE Class 10 Science Metals and Non metals Notes Set B_1

CHARACTERISTICS OF NON METALS

Some important characteristics of metals are :

* Nonmetals are soft solids, liquids or gases.

* Nonmetals (except graphite) are nonconductors of heat and electricity.

* Solid nonmetals are brittle.

* Nonmetals (except graphite and diamond) are low melting and low boiling.

* Nonmetals are electronegative elements. That is, nonmetals have a tendency to gain electrons and form negatively charged ions (called anions).

OCCURRENCE OF NONMETALS

Many nonmetals occur free in nature, whereas many more occur only in the form on their compounds as minerals.

The modes of occurrence of some typical nonmetal are described below :

CBSE Class 10 Science Metals and Non metals Notes Set B_2

Most nonmetals are either mined directly from their mines or obtained as by-products in some industrial
processes.

* Nitrogen and Oxygen are obtained from the air by fractional distillation of liquid air.

* Chlorine is obtained from common salt by electrolytic method.

* Sulphur is mined in its elemental form

* Nonmetals such as phosphorus and silica are obtained from their ores by chemical methods.

Physical Properties of Nonmetals

Some common general physical properties of nonmetals are given below :

Physical state : Nonmetals may occur as solids, liquids or gases at room temperature.

For example, under normal conditions, sulphur, phosphorus are solids, bromine is a liquid, whereas hydrogen, oxygen and nitrogen are gases.

Colour : Nonmetals come in many colours.

For example, sulphur is yellow, phosphorus is white, or red, chlorine is greenish-yellow, bromine is redish-brown. Hydrogen, oxygen and nitrogen are colourless.

Appearance : Nonmetals have dull appearance i.e., they do not shine. However, graphite and iodine are the only nonmetals which have metallic lustre.

Malleability and ductility : Nonmetals are neither ductile nor malleable. Nonmetals cannot be drawn into wires, and beaten into leaves/sheets.

Conductivity : Nonmetals do not conduct heat and electricity, i.e., nonmetals are insulators. Graphite however, is a good conductor of heat and electricity.

Density : Nonmetals usually have low densities and are soft. Diamond however is an exception. Diamond is the hardest natural substance known.

Tensile strength : Nonmetals have low tensile strength, i.e., Nonmetals can be easily broken.

Melting and boiling points : Nonmetals except graphite have low melting and boiling points.

Sound : Nonmetals do not produce sound when hit with an object, i.e., nonmetals are non-sonorous.

CHEMICAL PROPERTIES OF NONMETALS

Some general chemical properties of nonmetals are described below :

Electronegative Character

Nonmetals are electronegative elements. Nonmetals have a tendency to accept electrons and form negatively charged ions (anions).

CBSE Class 10 Science Metals and Non metals Notes Set B_3

Reaction with Oxygen

Nonmetals react with oxygen to give covalent oxides. Such oxides are either neutral or acidic in nature. Acids oxides of nonmetals dissolve in water to form corresponding acids. Reaction of some common nonmetals with oxygen are described below:

CBSE Class 10 Science Metals and Non metals Notes Set B_4

Sulphur : Sulphur on burning in air forms two oxides – sulphur dioxide (SO2) and sulphur trioxide (SO3).
Both these oxides are acidic. 
cbse-class-10-science-metals-and-non-metals-notes-set-c

Reaction with Hydrogen
Nonmetals react with hydrogen to form covalent hydrides. Thus in the hydrides of nonmetals, hydrogen is bonded to the nonmetal atom by covalent bonds. The hydrides of nonmetals atom by covalent bonds.
The hydrides of nonmetals do not conduct electricity. The hydrides of nonmetals may be acidic, basic or neutral depending upon the nature of the nonmetal.
For example, 
cbse-class-10-science-metals-and-non-metals-notes-set-c

Reaction with Acids
Nonmetals do not displace hydrogen from dilute acids. This is because nonmetals are able to give electron(s) for the reduction of H+. Some nonmetals however react with concentrated oxidising acids to form the corresponding oxyacids.
For example, sulphur reacts with conc. nitric acid to give sulphuric acid.
Sulphur + Nitric acid → Sulphuric acid + Nitrogen dioxide + Water
                (conc.)

Displacement Reactions
Certain more reactive nonmetals displace less reactive nonmetals from their salt solutions.
For example, Chlorine displaces bromine from bromides and iodine from iodies.
Potassium bromide + Chlorine → Potassium chloride + Bromine
Potassium iodide + Chlorine → Potassium chloride + Iodine

USES OF SOME COMMON NONMETALS 
Main uses of some common nonmetals are listed below : 
cbse-class-10-science-metals-and-non-metals-notes-set-c

OXIDES OF METALS AND NONMETALS
Both metals and nonmetals react with oxygen (present in the air) to form oxides. The oxides of metals and nonmetals differ in their properties.

Oxides of Metals
The oxides of metals are basic in nature. When dissolved in water, metal oxides give alkaline (or basic) solution which turn red litmus blue.
For example, magnesium (Mg) burns in air to give magnesium oxide (MgO), which is basic in nature. 
cbse-class-10-science-metals-and-non-metals-notes-set-c

Oxides of Nonmetals

The oxides of nonmetals are acidic in nature. When dissolved in water nonmetal oxides give acidic give solutions which turn blue litmus red.
For example, sulphur on burning in air, gives sulphur dioxide (SO2) which is acidic in nature.
cbse-class-10-science-metals-and-non-metals-notes-set-c

 
 
Chapter 02 Acids, Bases and Salts
CBSE Class 10 Chemistry Acids Bases And Salts Notes
Chapter 04 Carbon and Its Compounds
CBSE Class 10 Science Carbon And Its Compounds Notes
Chapter 05 Periodic Classification of Elements
CBSE Class 10 Science Periodic Classification Of Elements Notes
Chapter 10 Light Reflection and Refraction
CBSE Class 10 Science Light Reflection And Refraction Notes
Chapter 11 The Human Eye and Colourful World
CBSE Class 10 Science The Human Eye And The Colourful World Notes
Chapter 16 Sustainable Management of Natural Resources
CBSE Class 10 Science Sustainable Management Of Natural Resources Notes

More Study Material

CBSE Class 10 Science Chapter 3 Metals and Nonmetals Notes

We hope you liked the above notes for topic Chapter 3 Metals and Nonmetals which has been designed as per the latest syllabus for Class 10 Science released by CBSE. Students of Class 10 should download and practice the above notes for Class 10 Science regularly. All revision notes have been designed for Science by referring to the most important topics which the students should learn to get better marks in examinations. Studiestoday is the best website for Class 10 students to download all latest study material.

Notes for Science CBSE Class 10 Chapter 3 Metals and Nonmetals

Our team of expert teachers have referred to the NCERT book for Class 10 Science to design the Science Class 10 notes. If you read the concepts and revision notes for one chapter daily, students will get higher marks in Class 10 exams this year. Daily revision of Science course notes and related study material will help you to have a better understanding of all concepts and also clear all your doubts. You can download all Revision notes for Class 10 Science also from www.studiestoday.com absolutely free of cost in Pdf format. After reading the notes which have been developed as per the latest books also refer to the NCERT solutions for Class 10 Science provided by our teachers

Chapter 3 Metals and Nonmetals Notes for Science CBSE Class 10

All revision class notes given above for Class 10 Science have been developed as per the latest curriculum and books issued for the current academic year. The students of Class 10 can rest assured that the best teachers have designed the notes of Science so that you are able to revise the entire syllabus if you download and read them carefully. We have also provided a lot of MCQ questions for Class 10 Science in the notes so that you can learn the concepts and also solve questions relating to the topics. All study material for Class 10 Science students have been given on studiestoday.

Chapter 3 Metals and Nonmetals CBSE Class 10 Science Notes

Regular notes reading helps to build a more comprehensive understanding of Chapter 3 Metals and Nonmetals concepts. notes play a crucial role in understanding Chapter 3 Metals and Nonmetals in CBSE Class 10. Students can download all the notes, worksheets, assignments, and practice papers of the same chapter in Class 10 Science in Pdf format. You can print them or read them online on your computer or mobile.

Notes for CBSE Science Class 10 Chapter 3 Metals and Nonmetals

CBSE Class 10 Science latest books have been used for writing the above notes. If you have exams then you should revise all concepts relating to Chapter 3 Metals and Nonmetals by taking out a print and keeping them with you. We have also provided a lot of Worksheets for Class 10 Science which you can use to further make yourself stronger in Science

Where can I download latest CBSE Class 10 Science Chapter 3 Metals and Nonmetals notes

You can download notes for Class 10 Science Chapter 3 Metals and Nonmetals for latest academic session from StudiesToday.com

Can I download the Notes for Chapter 3 Metals and Nonmetals Class 10 Science in Pdf format

Yes, you can click on the link above and download notes PDFs for Class 10 Science Chapter 3 Metals and Nonmetals which you can use for daily revision

Are the revision notes available for Chapter 3 Metals and Nonmetals Class 10 Science for the latest CBSE academic session

Yes, the notes issued for Class 10 Science Chapter 3 Metals and Nonmetals have been made available here for latest CBSE session

How can I download the Chapter 3 Metals and Nonmetals Class 10 Science Notes pdf

You can easily access the link above and download the Class 10 Notes for Science Chapter 3 Metals and Nonmetals for each topic in Pdf

Is there any charge for the Class 10 Science Chapter 3 Metals and Nonmetals notes

There is no charge for the notes for CBSE Class 10 Science Chapter 3 Metals and Nonmetals, you can download everything free of charge

Which is the best online platform to find notes for Chapter 3 Metals and Nonmetals Class 10 Science

www.studiestoday.com is the best website from which you can download latest notes for Chapter 3 Metals and Nonmetals Science Class 10

Where can I find topic-wise notes for Class 10 Science Chapter 3 Metals and Nonmetals

Come to StudiesToday.com to get best quality topic wise notes for Class 10 Science Chapter 3 Metals and Nonmetals

Can I get latest Chapter 3 Metals and Nonmetals Class 10 Science revision notes as per CBSE syllabus

We have provided all notes for each topic of Class 10 Science Chapter 3 Metals and Nonmetals as per latest CBSE syllabus