CBSE Class 10 Chemistry Metals And Non Metals Worksheet Set B

Question : Halide ore out of the following is - 
(A) cinnabar
(B) horn silver
(C) limonite
(D) galena
Answer : B

Question : Which of the following is not a method for purification of metals ? 
(A) Calcination
(B) Distillation
(C) Liquation
(D) Sublimation
Answer : A

Question : Cu₂S + 2 Cu₂O → 6 Cu + SO₂ reaction occurs in - 
(A) calcination of copper
(B) roasting of copper
(C) smelting of copper
(D) bessemerisation of copper
Answer : D

Question : A non metal, which is found in liquid state is –
(A) bromine
(B) iodine
(C) oxygen
(D) carbon
Answer : A

Question : Which one of the following metal oxides shows both acidic and basic characters ?
(A) SO₂
(B) K₂O
(C) Cu₂O
(D) Al₂O₃
Answer : D

Question : Brass contains :
(A) Cu and Sn
(B) Cu and Ni
(C) Cu and Zn
(D) Mg and Al
Answer : A

Question : Which of the following cannot be used to extract a metal from its ore ? 
(A) Electrolytic reduction
(B) Carbon reduction
(C) Reaction with oxygen
(D) Reaction with more electropositive metal
Answer : C

Question : The composition of alloy, German silver is : 
(A) Copper, zinc and nickel
(B) Copper, tin and lead
(C) Copper, nickel and lead
(D) Copper, lead and silver
Answer : A

Question : In iron metallurgy, lime stone is used - 
(A) to obtain heat energy
(B) to reduce iron oxide into iron
(C) as an iron ore
(D) to remove sand (SiO₂)
Answer : D

Question : Gallium is in _______ state at room temperature -
(A) plasma
(B) liquid
(C) solid
(D) gaseous
Answer : C

Question : Which metal cannot displace hydrogen from dilute acids ? 
(A) Cu
(B) Mg
(C) Zn
(D) Na
Answer : A

Question : At room temperature liquid non-metal is- 
(A) carbon
(B) bromine
(C) mercury
(D) iodine
Answer : A

Question : Which alloy of aluminium is used for making aircrafts 
(A) Alnico
(B) Y-Alloy
(C) Duralumin
(D) Aluminium Bronze
Answer : B

Question : Which metal is known as ‘quick-silver’ - 
(A) Mercury
(B) Aluminium
(C) Antimony
(D) Strontium
Answer : C

Question : Iron ore is : 
(A) Bauxite
(B) Dolomite
(C) Haematite
(D) Calamine
Answer : A

Question : Which are alloys of brass ? 
(A) Ag + Cu
(B) Cu + Zn
(C) Zn + Fe
(D) Cu + Fe
Answer : C

Question : Which of the following is a relatively light metal ? 
(A) Lead
(B) Tin
(C) Aluminium
(D) Mercury
Answer : C

Question : What is the electronic configuration of sulphur ? 
(A) 2, 6, 8
(B) 2, 4, 8
(C) 2, 8, 6
(D) 2, 6, 4
Answer : C

Question : Match the following 
Column I                                                                  Column II
(a) strongest reducing agent in aqueous solution          I. Thalium
(b) Shows inert pair effect                                          II. Caesium
(c) Forms peroxide on heating with excess of oxygen    III. Lithium
(d) Used in photo cells                                                IV. Sodium
(A) a-IV, b-II, c-I, d-III
(B) a-III, b-I, c-IV, d-II
(C) a-III, b-II, c-I, d-IV
(D) a-II, b-IV, c-I, d-III
Answer : B

Question : About (i) H₂O₂, (ii) BaO₂, (iii) CO₂ the correct statement is :
(A) Both (i) and (ii) are peroxides, but not (iii)
(B) All are peroxides
(C) (i) is peroxide , but not (ii) and (iii)
(D) (i) and (iii) are peroxides, but not (ii)
Answer : A

Question : The composition of nicrom alloys is : 
(A) Cu, Ni, Cr
(B) Fe, Ni, Cr
(C) Al, Ni, Cr
(D) Mn, Ni, Cr
Answer : B

Question : In the following equation ‘x’ stands for 2Al + xH₂SO₄ → Al₂(SO₄)₃ + 3H₂ 
(A) 2
(B) 3
(C) 1
(D) 5
Answer : B

Question : The substance which are put into the blast furnace in the manufacture of iron :
(A) Iron ore, CaO, Ca(OH)₂ and CaSiO₃
(B) Iron ore, Coke, Like stone and CaSiO₃
(C) Iron ore, coke, Lime stone and Hot air
(D) Iron ore, CaO, Lime stone and hot air
Answer : C

Question : Match the following : 
a. Bleaching powder     (I) CaSO₄.2H₂O
b. Washing powder      (II) NaHCO₃
c. Plaster of paris        (III) Na₂CO₃
d. Gypsum                  (IV) CaOCl₂
                                  (V) CaSO₄.H₂O
(A) a-IV, b-III, c-V, d-I
(B) a-I, b-III, c-V, d-IV
(C) a-IV, b-V, c-III, d-I
(D) a-IV, b-III, c-II, d-V
Answer : A

Question : The metals which liberate hydrogen gas with dilute hydrochloric acid as well as caustic soda solution are :
(A) Na and K
(B) Zn and Al
(C) Fe and Mn
(D) Cu and Ag
Answer : B

Question : When a metal is alloyed with mercury the resulting alloy [Amalgum] will have :
(A) Less electrical conductivity than pure mtal
(B) Lower melting point than pure
(C) Both A and B are correct
(D) Both A and B are wrong
Answer : C

Question : The metal that can be obtained by electrolysis of an aqueous solution of its salts is :
(A) Zn
(B) Cr
(C) Mg
(D) Ca
Answer : B

Question : The process of coating of zinc over iron is known as .................
(A) Calcination
(B) Metallurgy
(C) Tinning
(D) Galvanisation
Answer : D

Question : Arrange the following metals in the order of their decreasing reactivity ?
Fe, Cu, Mg, Ca, Zn, Ag 
(A) Ca > Zn > Mg > Cu > Ag > Fe
(B) Ca > Zn > Cu > Mg > Ag > Fe
(C) Ca > Mg > Zn > Fe > Cu > Ag
(D) Ca > Mg > Fe > Zn > Cu > Ag
Answer : C

Question : Aluminium ore is.................. 
(A) Haematite
(B) Dolomite
(C) Bauxite
(D) Calamine
Answer : C

Question : In Haber’s process of Ammonia production, the element used as catalytic promotor to increase the activity of iron catalyst is ..................... 
(A) Ni (Nickel)
(B) W (Tungston)
(C) V (Vanadium)
(D) Mo (Molybednum)
Answer : D

Question : Which element forms maximum multiple bonds ? 
(A) N
(B) P
(C) As
(D) Bi
Answer : A

Question : Solder is an alloy of : 
(A) Cu + Zn
(B) Pb + Sn
(C) Pb + Sb
(D) Cu + Sn
Answer : B

Question : Which is the symbol of the element tungsten ?
(A) Ta
(B) Tc
(C) W
(D) V
Answer : C

Question : On additon of which metal the blue coloured copper sulphate solution turns into colourless solution ?
(A) Ag
(B) Hg
(C) Zn
(D) Au
Answer : C

Question : The oxide of which of the following element is not acidic : 
(A) Cl
(B) S
(C) K
(D) C
Answer : C

Question : A compound 'X' green coloured solid, gets oxidised to reddish brown solid in presence of air. 'X' on heating gives brown coloured solid 'Y' and two pungent gases 'A' and 'B' 'A' turns acidified potassium dichromate solution green, X, Y, A, B and type of reaction is : 
(A) CuSO₄, CuO, SO₂, SO₃ decomposition
(B) FeSO₄, Fe, SO₂, SO₃ Oxidation
(C) FeSO₄, Fe₂O3, SO₂, SO₃ decomposition
(D) FeSO₄, Fe₂O₃, SO₃, SO₂ decomposition
Answer : C

Question : The purpose of smelting an ore is to...........
(A) oxidize
(B) reduce
(C) neutralize
(D) decomposed
Answer : B

Question : Identify the wrong sequence of the element in a group
(A) Ca, Sr, Ba
(B) Cu, Au, Ag
(C) N, P, As
(D) Cl, Br, I
Answer : B

Question : In which of the following electrovalent compound both cation and anion represent the same inert gas configuration ? 
(A) Calcium bromide
(B) Magnesium chloride
(C) Strontium oxide
(D) Potassium sulphide
Answer : D

Question : Which of the following acid molecule differ from other molecule regarding their total number of valenece electrons ?
(A) HClO₄
(B) H₃PO₄
(C) HNO₃
(D) H₂ SO₄
Answer : C

Question : The technique through which Gold and Silver and refined ? 
(A) Electrolytic refining
(B) Vaccum melting
(C) Liquation process
(D) Zone refining
Answer : A

Question : This does not possess water of crystallization 
(A) Potassium nitrate
(B) Gypsum
(C) Copper sulphate
(D) Cobalt chloride
Answer : A

Question : Read the following statement and choose the correct option : 
(a) Calcium is present in the bones of animals and human beings as sulphate
(b) Heating Calcium carbonate to 1070K-1270K gives quick lime.
(c) Aluminium is not affected by dry air
(A) Only (a) and (c) are true
(B) Only (a) and (b) are true
(C) Only (b) and (c) are true
(D) all are true
Answer : C

Question : In the structure of Napthalene the difference between the number of sigma bonds and the number of pi bond is 
(A) 6
(B) 7
(C) 12
(D) 14
Answer : D

Question : When a clear aluminium article is made the anode and is electrolyzed with dil sulphuric acid to make a thicker protective and attractive oxide layer around it, then the process is called
(A) Galvanisation
(B) Anodising
(C) Leaching
(D) Thermite process
Answer : B

Question : A white coloured compound ‘XY’ is used in photochromic lenses. Choose the incorrect statement from the following: 
(A) The compound ‘XY’ decomposes into a metal and a non-metal on exposure to sunlight
(B) The compound ‘XY’ is completely soluble in aq. ammonia solution
(C) The metal part of ‘XY’ is grey coloured in elemental form
(D) The non-metal part of ‘XY’ is violet coloured in elemental form
Answer : D

Question : The percentage of carbon in steel is : 
(A) 0.1 to 1.5%
(B) 0.5 to 2.5%
(C) 2 to 5%
(D) 3 to 5%
Answer : A

Question : While preparing CO₂ in laboratory on which of the following substances hydrochloride acid is poured?
(A) Pieces of Zinc
(B) The practices of copper Sulphur
(C) Pieces of marble
(D) Ammonium Chloride
Answer : C

Question : A metal occurs in nature as its ore X which on heating in air converts to Y.Y reacts with unreacted X to give the metal. The metal is : 
(A) Hg
(B) Cu
(C) Zn
(D) Fe
Answer : B

Question : Assertion (A) : Nitrate ores are rarely available.
Reason (R) : Bond dissociationg energy of nitrogen is very high. 
(A) Both A and R are true and R is the correct explanation of A.
(B) Both A and R are correct but R is not the correct explanation of A.
(C) A is correct and R is false
(D) Both A and R are False
Answer : B

Question : Which metal is most reactive ?
(A) Na
(B) Ca
(C) K
(D) Zn
Answer : C

Question : Which metal does not react with oxygen at high temperature ? 
(A) Mg
(B) Al
(C) Ag
(D) Zn
Answer : C

Question : Can all minerals of a metal act as ores? Justify. 
Answer : Only those minerals can act as ores from which a metal can be conveniently and profitably extracted.

Answer : a. Platinum, gold and silver are used to make jewelry because of their bright shiny surface and high resistance to corrosion. Also they have high malleability and ductility.

b. Sodium, potassium and lithium are stored under oil to prevent their reaction with oxygen, moisture and carbon dioxide of air so as to protect them.

c. Aluminum metal forms a thin layer of aluminum oxide all over its surface under the action of moist air. This layer prevents the metal underneath from further corrosion. It is cheap, easily available, malleable and ductile. Therefore, it is used to make utensils for cooking.

d. It is easier to obtain a metal from its oxides as compared to its sulphides and carbonates. So, prior to reduction, metal carbonate and sulphides must be converted into metal oxides. A carbonate ore is converted into oxide by calcination whereas a sulphide ore is converted into oxide by roasting.

e. When copper vessels are exposed to moist air, they form a green coating of basic copper carbonate

[CuCO₃ .Cu(OH)₂].

The sour substances such as lemon or tamarind juice contain acids. Lemon juice contains citric acid and tamarind contains tartaric acid. These acids dissolve the coating of copper oxide or basic copper carbonate present on the surface of tarnished copper vessels and make them shining red-brown again.

Question : When a metal X is treated with cold water, it gives a basic salt Y with molecular formula XOH (molecular mass = 40) and liberates a gas Z which easily catches fire. Identify X, Y and Z and also write the reaction involved.
Answer :  X is Na, Y is NaOH and Z is H₂. The reaction is: 2Na + 2H2O → 2NaOH + H2 + Heat energy It is given that the molecular formula of Y = XOH and molecular mass = 40.
Let the atomic weight of metal X be a.
Then, molecular mass of XOH = a + 16 + 1 = 40.
Then, a = 40 – 17 = 23.
The atomic weight of sodium is 23, so metal X is sodium (Na).
Sodium reacts with water to give hydrogen gas (Z), that catches fire.
2Na + 2H₂O(Cold) → 2NaOH + H₂↑
So, metal X is sodium (Na), Y is (sodium hydroxide) and Z is H2 (hydrogen gas).

Question : When most of the metals are treated with nitric acid, they do not produce hydrogen gas. Why? 
Answer :  Nitric acid is a strong oxidising agent. When hydrogen gas is formed in a reaction between a metal and dilute nitric acid, the nitric acid oxidises this hydrogen to form water. So, in reactions between metals with dilute nitric acid, no hydrogen gas is evolved.

Question : Of the three metals X, Y and Z, X reacts with cold water, Y with hot water and Z with steam only. Identify X, Y and Z and also arrange them in increasing order of reactivity.
Answer :  X is alkali metal, Na or K. Y is alkaline earth metal, Mg or Ca. Z is Fe.
X reacts with cold water, so it must be very reactive like alkali metals, like sodium. Sodium reacts with water to form sodium hydroxide and hydrogen gas.
2Na + 2H₂O → 2NaOH + H₂
Y metal can react with hot water, so it must be a little less reactive than X i.e., alkaline Earth metal. So, Y can be magnesium (Mg) which reacts with hot water to form magnesium
hydroxide.
Mg + 2H₂O → Mg(OH)₂ + H₂
Z metal which reacts with steam must be iron that forms iron (III) oxide with steam.
3Fe + 4H₂O → Fe₃O₄ + 4H₂
Hence, the increasing order of reactivity of the given metals is:
Z (Fe) < Y (Mg) < X (Na)

Question : A shining metal ‘M‘, on burning gives a dazzling white flame and changes to a white powder ‘N‘.
(A) Identify ‘M‘ and ‘N‘.
(B) Represent the above reaction in the form of a balanced chemical equation.
(C) Does ‘M‘ undergo oxidation or reduction in this reaction? Justify. 
Answer :  (A) M—Magnesium
N—Magnesium oxide.
(B) 2Mg(s)     +       O₂(g)   →        2MgO(s)
      magnesium        oxygen       magnesium oxide
Or\2M + O₂ → 2MO₂
(C) ‘M‘ metal will undergo oxidation reaction as oxygen is added to metal ‘M‘ and MO2 (metal oxide) is formed.
Explanation: When a piece of shining metal ‘M‘ is burnt in air, a white powder of metal oxide is formed. Shining metal is magnesium ribbon which burns with a dazzling white
flame and white powder is formed which is magnesium oxide.

Question : (A) Complete and balance the following chemical equations:
(i) Al₂O₃ + HCl →
(ii) K₂O + H₂O →
(iii) Fe + H₂O →
(B) An element ‘X‘ displaces iron from the aqueous solution of iron sulphate. List your observations if the element ‘X‘ is treated with the aqueous solutions of copper sulphate, zinc sulphate and silver nitrate. Based on the observations arrange X, Zn, Cu and Ag in increasing order of their reactivities. 
Answer :  (A) (i) Al₂O₂(s)        +     6HCl(l)   →
          (Aluminium oxide)      (Hydrochloric acid)
                                                       2AlCl₃(aq)(l)        +      3H₂O(l)
                                                       Aluminium chloride       water
(ii) K₂O        +       H₂O(l)    →    2KOH(aq)             +   4H₂(g)
   (Pot. oxide)      (Water)         Potassium hydroxide

(iii) 3Fe(s)      +    4H₂O(g) →    Fe₃O₄(s)   +   4H₂(g)
    Iron (steam)                   Iron (II, III) oxide  (Hydrogen)

Question : A non-metal X exists in two different forms Y and Z. Y is the hardest natural substance, whereas Z is a good conductor of electricity. Identify X, Y and Z. 
Answer :  Here, X is carbon; Y is diamond and Z is graphite.
Non-metal X is carbon (C).
Carbon exists in different forms. These different forms of carbon are called the allotropes of carbon. Diamond and graphite are allotropes of carbon.
Y is diamond because diamond is the hardest natural substance.
Z is graphite as it is a good conductor of electricity due to the presence of free mobile electrons.

Question : Explain the following:
(A) Sodium chloride is an ionic compound which does not conduct electricity in solid state, whereas it does conduct electricity in molten state as well as in aqueous solution.
(B) Reactivity of aluminium decreases if it is dipped in nitric acid.
(C) Metals like calcium and magnesium are never found in their free state in nature 
Answer :  (A) We know that solid sodium chloride is made up of ions but it does not conduct electricity. This is because of the fact that the sodium ions and chloride ions are held together in fixed positions in the sodium chloride crystal. They cannot move freely.
When sodium chloride is dissolved in water to make aqueous solution, it becomes a good conductor of electricity. On dissolving in water, the sodium chloride crystal breaks, sodium ions (Na+) and chloride ions (Cl–) become free to move and as a result conduct electricity.
(B) A layer of aluminium oxide is formed on the metal when aluminium is dipped in nitric acid. This happens because nitric acid is a strong oxidizing agent. The layer of aluminium oxide acts as a barrier to prevent further reaction of aluminium. As a result, the reactivity of aluminium decreases.
(C) Metals like calcium and magnesium are never found in free state in nature because these metals are very reactive and readily combine with other elements to form a compound.

Question : Write the balanced chemical equation for the following reactions and identify the type of reaction in each case:
(A) In Thermite reaction, iron (III) oxide reacts with aluminium and gives molten iron and aluminium oxide.
(B) Magnesium ribbon is burnt in an atmosphere of nitrogen gas to form solid
C) Chlorine gas is passed in an aqueous potassium iodide solution to form potassium chloride solution and solid odine.
Answer :  (A) Thermite reaction, iron (III) oxide reacts with aluminium and gives molten iron and aluminium oxide.
Fe₂O₃(s) + 2Al(s) → ₂Fe(l) + Al₂O₃(s)
Iron (III) oxide Iron Aluminium oxide + Heat + Light
It is an exothermic redox reaction as well as displacement reaction because aluminium displaces iron from iron (III) oxide.

Question : Which of the following has electrovalent bond(s)?

Question : During smelting, an additional substance is added which combines with impurities to form a fusible product known as: 

a. Flux

b. Slag

c. Gangue

d. Mud

Answer : B 

Explanation: During the smelting of iron, limestone is added as a flux. The temperature inside the blast furnace decomposes limestone to calcium oxide which removes silicate impurity. Impurities like silicon are passed into the slag.

The metal is separated from the molten slag.

CaCO₃ à CaO + CO₂ ; CaO + SiO₂ à CaSiO₃ (Slag)

 

Question : Match the following with the correct response: 

(1) Enrichment of ore (A) Froth floatation process

(2) Extraction of metals (B) Reduction by carbon

(3) Conversion of oxide form to the metallic form (C) Roasting

(4) Refining of metals (D) Electrolysis

a. 1-C, 2-B, 3-D, 4-A

b. 1-B, 2-D, 3-A, 4-C

c. 1-A, 2-C, 3-B, 4-D

d. 1-D, 2-A, 3-C, 4-B

Answer : C 

Explanation: Froth floatation process is a process employed for the concentration or enrichment of a sulphide ore. Roasting is used for the conversion of ore to metal oxide. Reduction by carbon is used for the conversion of oxide to the metallic form. Electrolysis is employed for the

refining of metal like copper.

Question : Give the formulae of the stable binary compounds that would be formed by the combination of following pairs of elements:
(A) Mg and N₂ (B) Li and O₂
(C) Al and Cl₂ (D) K and O₂ 
Answer :  (A) Mg and N2 Mg3N2 (Magnesium nitride)
(B) Li and O₂ Li₂O (Lithium oxide)
(C) Al and Cl₂ AlCI₃ (Aluminium chloride)
(D) K and O₂ K₂O (Potassium oxide)

Question : A metal M forms an oxide having the formula M2O3. It is dissolved both in dilute sulphuric and dilute sodium hydroxide solution. Identify the metal and write equations for the reaction involved. What criteria would you use to assess it?
Answer :  Here the metal oxide dissolves in sulphuric as well as sodium hydroxide solution. That means metal oxide is showing acidic as well as basic character. So metal oxide is amphoteric oxide.
The metal is Aluminium (Al).
It forms aluminium oxide (Al2O 3) which is amphoteric that it shows the nature of both acidic and basic.
Al2O₃  +  3H2SO₄    →   Al2(SO₄)₃   +   3H₂O
                                        Salt
Al₂O₃  +  6NaOH      →     2NaAlO₂      +    H₂O
                                           Salt

Question : (A) What are amphoteric oxides? Choose the amphoteric oxides from amongst the following oxides: Na₂O, ZnO, Al₂O₃, CO₂, H₂O.
(B) Why is it that non-metals do not displace hydrogen from dilute acids? 
Answer :  (A) Those metal oxides which show basic as well as acidic behaviour are known as amphoteric oxides. Amphoteric oxides react with both acids as well as bases to form salts and water. Al2O3, ZnO are amphoteric oxides among the given oxides.
(B) Non-metals do not displace hydrogen from dilute acids because in order to displace hydrogen ions (H+) of an acid and convert them into hydrogen gas, electrons should be supplied to the hydrogen ions (H+) of the acid.
A non-metal is itself an acceptor of electrons. Hence it cannot give electrons to the hydrogen ions of the acid to reduce them to hydrogen gas. As a result, non- metals are not able to displace hydrogen ions from acids to form hydrogen gas.

Question : Name one metal and one non-metal that exist in liquid state at room temperature. Also name two metals having melting point less than 310 K (37°C). 
Answer :  (1) Metal that exists in liquid state at room temperature is mercury.
(2) Non-metal that exists in liquid state at room temperature is bromine.
(3) Metals having melting point less than 310 K are cesium (Cs) and gallium (Ga).

Question : (A) When calcium metal is added to water, the gas evolved does not catch fire but the same gas evolved on adding potassium metal to water catches fire. Explain.
(B) Name a metal for each case:
(i) It displaces hydrogen gas from nitric acid.
(ii) It does not react with any physical state of water.
(iii) It does not react with cold as well ashot water but reacts with steam. 
Answer :  (A) More heat is evolved during the reaction of potassium metal with water due to which the hydrogen gas formed catches fire. Onthe other hand, less heat is evolved during
the reaction of calcium metal with water,which cannot make the hydrogen gas burn.
(B) (i) Zinc because it is more reactive than hydrogen and can easily displace hydrogen from its compounds like water and acids to form hydrogen gas.
(ii) Copper because it is a highly unreactive metal.
(iii) Iron because it is a very less reactive metal.

Question : When a metal X is  treated with cold water, it gives a basic salt Y with molecular formula XOH (molecular mass = 40) and liberates a gas Z which easily catches fire. Identify X, Yand Z and also write the reaction involved.
Answer :  Given, molecular formula of Y = XOH and molecular mass of Y = 40
So, atomic mass of metal X would be,
M + 16 + 1 = 40
M = 40 – 17 = 23
Metal with atomic mass 23 is sodium(Na) and reaction of it with cold water will form the base sodium hydroxide (NaOH) and liberates H2 gas which easily catches fire.
2Na + 2H2O(Cold) → 2NaOH + H₂
X = Sodium (Na)
Y = Sodium hydroxide (NaOH)
Z = Hydrogen gas (H₂) 

Question :  Name two elements that are alloyed with iron to make stainless steel. 
Answer : Nickel and chromium are used with iron to form stainless steel.

Sodium is obtained by the electrolysis of its molten chloride (Sodium chloride). The sodium metal is deposited at the cathode (the negatively charged electrode), whereas chlorine is liberated at the anode (the positively charged electrode).