Class 7 Chemistry Solved Model Papers: ICSE Class 7 Chemistry Sample Paper with Solutions Set 02
Explore authentic exam practice materials through the ICSE Class 7 Chemistry Sample Paper with Solutions Set 02. Tailored for Class 7 learners, utilizing these Chemistry sample papers ensures thorough preparation and strengthens time management skills before final ICSE evaluations.
Download Class 7 Chemistry Sample Paper PDF
Navigate directly to the solved Chemistry model papers using the digital viewer below. Each practice set includes detailed solutions, allowing students to instantly cross-check their work and identify areas requiring further revision.
Question 1
Choose the correct answer out of the four available choices given under each question. [15]
1. ________ is used during fermentation. [1 Mark]
(A) Yeast
(B) Fungi
(C) Bacteria
(D) Microorganism
Answer: (A) Yeast
Yeast acts as a biocatalyst during the fermentation of sugars into alcohol and carbon dioxide.
Teacher's Note:
a) Yeast produces enzymes like zymase which facilitate fermentation.
b) Do not confuse yeast with general bacteria used in dairy products.
2. _______ is an endothermic change. [1 Mark]
(A) Burning of coal
(B) Glowing of an electric lamp
(C) Dissolving calcium oxide in water
(D) Evaporation of ammonium chloride in water
Answer: (D) Evaporation of ammonium chloride in water
Endothermic changes absorb heat from the surroundings during the process.
Teacher's Note:
a) Dissolving certain salts like ammonium chloride absorbs thermal energy, lowering the solution temperature.
b) Burning of coal and dissolving calcium oxide are highly exothermic processes.
3. A non-metal stored in water is? [1 Mark]
(A) Sulphur
(B) Iodine
(C) Carbon
(D) Phosphorus
Answer: (D) Phosphorus
White phosphorus is extremely reactive and catches fire spontaneously in air, so it is stored under water.
Teacher's Note:
a) Phosphorus has a very low ignition temperature (around 30 degrees Celsius).
b) Sodium and potassium are metals stored in kerosene, whereas white phosphorus is a non-metal stored in water.
4. Which of the following is used in the preparation of mortar? [1 Mark]
(A) Calcium hydroxide
(B) Sodium hydroxide
(C) Potassium hydroxide
(D) Copper hydroxide
Answer: (A) Calcium hydroxide
Calcium hydroxide (slaked lime) is mixed with sand and water to prepare mortar for construction.
Teacher's Note:
a) Slaked lime sets slowly by absorbing carbon dioxide from the air to form hard calcium carbonate.
b) Remember common chemical names like slaked lime for calcium hydroxide.
5. A chemical reaction in which heat is evolved is called ______. [1 Mark]
(A) Endothermic reaction
(B) Precipitation reaction
(C) Exothermic reaction
(D) Electrolysis
Answer: (C) Exothermic reaction
Exothermic reactions release thermal energy into the surroundings.
Teacher's Note:
a) The prefix 'exo' means outside or exiting, indicating release of heat.
b) Combustion and neutralization are classic examples of exothermic reactions.
6. ________ is used in soft drinks. [1 Mark]
(A) Sulphuric acid
(B) Carbonic acid
(C) Hydrochloric acid
(D) Acetic acid
Answer: (B) Carbonic acid
Carbonic acid gives the characteristic fizz and slightly acidic taste to carbonated soft drinks.
Teacher's Note:
a) Carbonic acid is formed when carbon dioxide is dissolved under pressure in water.
b) Mineral acids like sulphuric and hydrochloric acids are highly corrosive and never used in food items.
7. Sulphur dioxide is ________ in water. [1 Mark]
(A) Highly soluble
(B) Fairly soluble
(C) Slightly soluble
(D) Insoluble
Answer: (A) Highly soluble
Sulphur dioxide dissolves readily in water to form sulphurous acid.
Teacher's Note:
a) High solubility of acidic gases in atmospheric moisture is the primary cause of acid rain.
b) Memorize solubility characteristics of common laboratory gases.
8. Who first stated that 'atoms contain negatively charged particles called electrons'? [1 Mark]
(A) John Dalton
(B) J. J. Thomson
(C) Goldstein
(D) E. Rutherford
Answer: (B) J. J. Thomson
J. J. Thomson discovered the electron using cathode ray tube experiments and proposed the plum pudding model.
Teacher's Note:
a) Dalton originally stated that atoms were indivisible particles.
b) Goldsteins discovered protons (canal rays), while Rutherford discovered the atomic nucleus.
9. Kerosene can be separated from water using a _________ [1 Mark]
(A) Separating Funnel
(B) Centrifuge
(C) Filter paper
(D) Sieve
Answer: (A) Separating Funnel
Kerosene and water are immiscible liquids with different densities, making a separating funnel the ideal apparatus.
Teacher's Note:
a) The denser liquid forms the lower layer and is drained out first through the stopcock.
b) Centrifuges are used for suspended colloidal particles like cream in milk.
10. Gun powder is a mixture of _______. [1 Mark]
(A) Sulphur, carbon and potassium nitrate
(B) Carbon, sulphur and potassium nitrate
(C) Sulphur, oxygen and potassium nitrate
(D) Oxygen, carbon and potassium nitrate
Answer: (A) Sulphur, carbon and potassium nitrate
Gunpowder consists of a precise mechanical mixture of sulphur, charcoal (carbon), and potassium nitrate (saltpeter).
Teacher's Note:
a) Both options (A) and (B) list the same three components; option (A) is the standard textbook order.
b) Gunpowder is a mixture, not a chemical compound, so its components retain their individual properties.
11. A molecule of an element composed of more than three atoms is known as [1 Mark]
(A) Monoatomic molecule
(B) Diatomic molecule
(C) Triatomic molecule
(D) Polyatomic molecule
Answer: (D) Polyatomic molecule
Molecules containing four or more atoms per molecule are classified as polyatomic molecules (such as P4 or S8).
Teacher's Note:
a) Monoatomic molecules contain one atom (noble gases), diatomic contain two (O2), and triatomic contain three (O3).
b) Pay close attention to atomicity prefixes.
12. Petroleum is refined using ______. [1 Mark]
(A) Filtration
(B) Sedimentation
(C) Distillation
(D) Evaporation
Answer: (C) Distillation
Fractional distillation is used to separate the various useful components of crude petroleum based on their boiling points.
Teacher's Note:
a) Fractional distillation involves repeated condensation and vaporization across a fractionating column.
b) Simple filtration only separates insoluble solids from liquids.
13. Precipitation reactions always take place in [1 Mark]
(A) Solid state
(B) Gaseous state
(C) Solutions
(D) All states
Answer: (C) Solutions
Precipitation reactions involve mixing two aqueous ionic solutions to form an insoluble solid product (precipitate).
Teacher's Note:
a) Ions must be mobile in a solution medium to react and form an insoluble salt.
b) Always mention state symbols like (aq) and (s) when writing precipitation equations.
14. During chlorination, ________ chemicals are used. [1 Mark]
(A) Chlorine
(B) Ozone
(C) Bleaching powder
(D) All of the above
Answer: (D) All of the above
Water disinfection methods broadly categorized under chlorination or general disinfection utilize chlorine gas, ozone, or bleaching powder.
Teacher's Note:
a) Chlorine compounds and ozone are powerful oxidizing agents that destroy harmful pathogens in water supplies.
b) Read comprehensive textbook definitions where overarching terms include multiple specific examples.
15. Heating of copper carbonate forms _______. [1 Mark]
(A) Carbon dioxide
(B) Copper oxide
(C) Carbon dioxide and copper oxide
(D) Carbon oxide and copper dioxide
Answer: (C) Carbon dioxide and copper oxide
Thermal decomposition of green copper carbonate yields black copper oxide and carbon dioxide gas.
Teacher's Note:
a) Equation: CuCO3 → CuO + CO2.
b) Note the correct chemical names and formulae to avoid confusion with carbon monoxide.
Question 2
(A) Give a scientific word for the following: [5]
1. The change of a solid into liquid [1 Mark]
Answer: Melting (or Fusion).
Teacher's Note:
a) Melting is the phase transition from solid to liquid at a fixed temperature called the melting point.
b) Ensure proper scientific terminology is used instead of general descriptions.
2. An apparatus used for collecting gases and holding them in captivity. [1 Mark]
Answer: Gas jar.
Teacher's Note:
a) A gas jar is a standard laboratory glass container used with a cover plate to collect gases.
b) Students must identify standard laboratory apparatus correctly.
3. The type of chemical reaction in which a more reactive element displaces a less reactive element from its compound. [1 Mark]
Answer: Displacement reaction.
Teacher's Note:
a) Single displacement reactions depend on the reactivity series of metals and non-metals.
b) A more reactive metal displaces a less reactive metal from its salt solution.
4. A substance used to speed up or slow down the chemical reactions without taking part in the reaction. [1 Mark]
Answer: Catalyst.
Teacher's Note:
a) Catalysts alter the rate of a chemical reaction without undergoing any permanent chemical change themselves.
b) Catalysts that slow down reactions are called negative catalysts or inhibitors.
5. The process by which two miscible liquids are separated [1 Mark]
Answer: Fractional distillation.
Teacher's Note:
a) Fractional distillation is used when the boiling point difference between miscible liquids is relatively small.
b) Simple distillation is used when the boiling point difference is large.
(B) Fill in the blanks: [5]
1. The flow of air from land to sea at night is called ________. [1 Mark]
Answer: Land breeze.
Teacher's Note:
a) Land cools faster than the sea at night, creating high pressure on land and low pressure over the sea, causing air to flow from land to sea.
b) Daytime air flow from sea to land is called a sea breeze.
2. _________ is based on the tendency of insoluble solid particles to settle down in an insoluble solid-liquid mixture. [1 Mark]
Answer: Sedimentation.
Teacher's Note:
a) Sedimentation allows heavier suspended solid particles to settle at the bottom under gravity.
b) It is typically followed by decantation or filtration.
3. _________ state of a substance has definite shape.. [1 Mark]
Answer: Solid.
Teacher's Note:
a) Solids possess tightly packed particles with strong intermolecular forces, giving them a fixed shape and volume.
b) Liquids and gases do not have a definite shape.
4. An ion with positive charge is called________. [1 Mark]
Answer: Cation.
Teacher's Note:
a) Cations are formed by the loss of electrons from neutral atoms (usually metals).
b) Negatively charged ions are called anions.
5. __________ is the most abundant inert gas present in air. [1 Mark]
Answer: Argon.
Teacher's Note:
a) Argon makes up approximately 0.93% of the Earth's atmosphere by volume.
b) It is the most abundant noble gas in the atmosphere, followed by neon and helium.
Question 3
(A) Match the item in Column A with the appropriate item in Column B. [5]
| Column A | Column B |
|---|---|
| Common salt | NaCl |
| Marble | CaCO3 |
| Sand | SiO2 |
| Baking soda | NaHCO3 |
| Calcium hydroxide | Ca(OH)2 |
Teacher's Note:
a) Matching questions require exact pairing of chemical names with their correct chemical formulas.
b) Common salt is sodium chloride (NaCl) and sand is silicon dioxide (SiO2).
(B) Give one example each for the following: [5]
1. Gas with pungent odour [1 Mark]
Answer: Sulphur dioxide (or Ammonia).
Teacher's Note:
a) Sulphur dioxide has a suffocating smell resembling burning sulphur.
b) Ammonia also has a strong, pungent, choking smell.
2. Heterogeneous mixture [1 Mark]
Answer: Oil in water (or Sand and water).
Teacher's Note:
a) A heterogeneous mixture has non-uniform composition and visible boundaries between components.
b) Immiscible liquids and solid-liquid suspensions are classic examples.
3. Element with valency 4 [1 Mark]
Answer: Carbon (or Silicon).
Teacher's Note:
a) Carbon has an atomic number of 6 with electronic configuration 2, 4, giving it a valency of 4 (tetravalent).
b) Silicon is another common tetravalent element belonging to the same group.
4. A gas used in air balloon [1 Mark]
Answer: Helium (or Hydrogen).
Teacher's Note:
a) Helium is lightweight, non-flammable, and safe for filling weather and party balloons.
b) Although hydrogen is lighter, helium is preferred due to its non-combustible nature.
5. A component of air which helps in controlling the rate of evaporation [1 Mark]
Answer: Water vapour.
Teacher's Note:
a) Humidity (water vapour content in air) determines how fast liquid water evaporates.
b) Higher humidity slows down the rate of evaporation.
Question 4
(A) Match the following: [5]
| Column A | Column B |
|---|---|
| Enameling | Baking a mixture of silicates |
| Painting | Red lead oxide paint |
| Galvanisation | Iron sheets dipped in molten zinc |
| Tinning | Iron sheets dipped in molten tin |
| Chromeplating | Iron articles electroplated with chromium |
Teacher's Note:
a) These methods are used to prevent the rusting and corrosion of iron.
b) Galvanisation uses zinc coating, while tinning uses molten tin.
(B) Match the following: [5]
| Column A | Column B |
|---|---|
| The constituent of air which is around 0.02% | Carbon dioxide |
| The constituent of air which is non-combustible, non-supporter of combustion | Nitrogen |
| The constituent of air which is non-combustible, but supports combustion | Oxygen |
| A pollutant in air responsible for acid rain | Sulphur dioxide |
| The main rare gas present in air | Argon |
Teacher's Note:
a) Students should accurately memorize atmospheric gas percentages and properties.
b) Oxygen supports combustion, whereas nitrogen does not support combustion.
Question 5
(A) State the differences between [5]
1. Physical and Chemical changes [2½ Marks]
Answer:
| Physical Changes | Chemical Changes |
|---|---|
| Physical changes are temporary and reversible. | Chemical changes are permanent and irreversible. |
| During a physical change, no new substance is formed. | During a chemical change, a new substance is formed. |
| The composition and properties of the original substance are not altered. | The composition and properties of the original substance are altered. |
| Example: Boiling of water or melting of wax. | Example: Curdling of milk or burning of paper. |
Teacher's Note:
a) The key distinction is whether a new chemical substance is formed.
b) Always provide tabular comparisons with examples for clarity.
2. Metals and non-metals [2½ Marks]
Answer:
| Metals | Non-metals |
|---|---|
| Metals have luster and can be polished. | Non-metals do not have luster (except iodine and graphite). |
| Metals are malleable and ductile. | Non-metals are brittle, non-malleable, and non-ductile. |
| Metals are good conductors of heat and electricity. | Non-metals are poor conductors of heat and electricity (except graphite). |
| Example: Iron, Copper, Aluminium. | Example: Sulphur, Carbon, Oxygen. |
Teacher's Note:
a) Physical properties like malleability, ductility, and conductivity distinguish metals from non-metals.
b) Exceptions like graphite and iodine should be remembered.
(B) Give the applications of the following methods used for separation of substances. [5]
1. Sedimentation [1 Mark]
Answer: Sedimentation is used for obtaining clear water from muddy water and in municipal water purification plants to settle suspended impurities.
Teacher's Note:
a) Sedimentation relies on gravity to separate heavier suspended insoluble particles.
b) Alum is often added (loading) to speed up sedimentation.
2. Filtration [1 Mark]
Answer: Filtration is used in kitchens for preparing tea, in coffee machines to filter out coffee grounds, and in water treatment plants for drinking water.
Teacher's Note:
a) Filtration separates insoluble solid particles from a liquid using a porous barrier.
b) Filter paper is commonly used in laboratory filtration setups.
3. Evaporation [1 Mark]
Answer: Evaporation is used for obtaining common salt from sea water, drying clothes, and preparing solid salts in the laboratory.
Teacher's Note:
a) Evaporation converts a liquid into its vapor, leaving behind the dissolved solid solute.
b) It is useful when the solvent component is not required to be recovered.
4. Distillation [1 Mark]
Answer: Distillation is used to prepare pure distilled water, in laboratory experiments involving salt separation, and for separating petroleum fractions during refining.
Teacher's Note:
a) Distillation involves vaporization followed by condensation, allowing both solvent and solute recovery.
b) Fractional distillation handles mixtures with closely boiling liquid components.
5. Centrifugation [1 Mark]
Answer: Centrifugation is used for separating cream from milk in dairies and for separating red blood cells (RBCs) from blood samples in laboratories.
Teacher's Note:
a) Centrifugation uses high-speed rotational force to separate particles based on density.
b) Denser particles are forced outward/downward faster than in normal gravity sedimentation.
Question 6
(A) State whether True or False. [5]
1. Ammonia is acidic in nature. [1 Mark]
Answer: False. Ammonia is basic in nature.
Teacher's Note:
a) Aqueous ammonia turns red litmus blue, indicating basic (alkaline) properties.
b) Read statements carefully before marking true or false.
2. When water is added to quick lime, an exothermic reaction takes place and a large amount of heat is produced. [1 Mark]
Answer: True.
Teacher's Note:
a) CaO + H2O → Ca(OH)2 + Heat.
b) This slaking of lime releases significant thermal energy, causing the water to boil.
3. The force of attraction between the molecules in solids is maximum. [1 Mark]
Answer: True.
Teacher's Note:
a) Strong intermolecular forces in solids hold particles in fixed, rigid positions.
b) Intermolecular forces are moderate in liquids and negligible in gases.
4. Metals have positive valency. [1 Mark]
Answer: True.
Teacher's Note:
a) Metals lose valence electrons to form positively charged ions (cations).
b) Non-metals generally exhibit negative valencies by gaining electrons.
5. Evaporation cannot take place at room temperature. [1 Mark]
Answer: False. Evaporation can take place at any temperature below the boiling point.
Teacher's Note:
a) Surface molecules with higher kinetic energy escape into the vapor phase at room temperature.
b) Puddles dry up and wet clothes dry even without boiling water.
(B) Write the symbols for the following elements: [5]
| Element | Symbol |
|---|---|
| Helium | He |
| Silver | Ag |
| Gold | Au |
| Tin | Sn |
| Aluminium | Al |
Teacher's Note:
a) Chemical symbols are derived from English or Latin names (e.g., silver is Argentum, gold is Aurum, tin is Stannum).
b) Note the correct capitalization of chemical symbols (first letter capital, second letter lowercase).
Question 7
(A) Give the chemical formula for the following compounds: [5]
| Compound | Chemical formula |
|---|---|
| Nitrogen dioxide | NO2 |
| Dinitrogen oxide | N2O |
| Calcium hydroxide | Ca(OH)2 |
| Copper sulphate | CuSO4 |
| Carbonic acid | H2CO3 |
Teacher's Note:
a) Chemical formulas are written by balancing the valencies of combining radicals.
b) Notice that the question paper's printed table had misaligned answers in the OCR, which are correctly matched here based on standard chemical nomenclature .
(B) Balance the following reactions: [5]
1. Mg + O2 → MgO [1 Mark]
Answer: 2Mg + O2 → 2MgO
Teacher's Note:
a) Balance oxygen atoms first by placing a coefficient of 2 before MgO, then balance Mg atoms.
b) Law of Conservation of Mass must hold true for all balanced chemical equations.
2. 2H2O → 2H2 + O2 [1 Mark]
Answer: 2H2O → 2H2 + O2
Teacher's Note:
a) This represents the electrolysis of water into hydrogen and oxygen gases.
b) Placing a coefficient of 2 before H2O and H2 balances both hydrogen and oxygen.
3. Fe + CuSO4 → FeSO4 + Cu [1 Mark]
Answer: Fe + CuSO4 → FeSO4 + Cu
Teacher's Note:
a) This is already a balanced single displacement reaction.
b) Iron displaces copper from copper sulphate solution because iron is more reactive than copper.
4. NaHCO3 + H2SO4 → Na2SO4 + H2O + 2CO2 [1 Mark]
Answer: 2NaHCO3 + H2SO4 → Na2SO4 + 2H2O + 2CO2
Teacher's Note:
a) Balance sodium atoms first by putting 2 before NaHCO3.
b) Adjust water and carbon dioxide coefficients to balance hydrogen and oxygen atoms completely.
5. Zn + HCl → ZnCl2 + H2 [1 Mark]
Answer: Zn + 2HCl → ZnCl2 + H2
Teacher's Note:
a) Place a coefficient of 2 before HCl to balance chlorine and hydrogen atoms.
b) This is a standard laboratory method for preparing hydrogen gas using an active metal and dilute acid.
Free study material for Chemistry
Download ICSE Sample Papers: Class 7 Chemistry
Download Sample Paper: ICSE Class 7 Chemistry Sample Paper with Solutions Set 02 (Class 7 Chemistry)
Review model practice papers for Class 7 Chemistry. Working through the ICSE Class 7 Chemistry Sample Paper with Solutions Set 02 under simulated test conditions at home ensures complete familiarity with upcoming school evaluations.
Why Practice Class 7 Chemistry Sample Papers?
- Original Practice Material: Access unique questions for Chemistry designed to challenge your understanding.
- Self-Assessment: Evaluate scores per set to pinpoint weak zones in Class 7 Chemistry.
- Exam Completion Skills: Routine problem sets train you to manage test duration efficiently without stress.
Steps to Follow After Completing ICSE Class 7 Chemistry Sample Paper with Solutions Set 02
- Verify Answers: Compare your responses against professional teacher solutions provided in the sample paper keys.
- Error Analysis: Class 7 learners must review incorrect answers carefully to understand underlying mistakes.
- Concept Reinforcement: Consult the official NCERT book for Class 7 Chemistry when stuck before re-attempting problems.
FAQs
You can download the complete PDF for ICSE Class 7 Chemistry Sample Paper with Solutions Set 02 for free from StudiesToday.com. Our resources for Class 7 Chemistry are updated for the latest academic session and follow the official exam pattern.
Yes, ICSE Class 7 Chemistry Sample Paper with Solutions Set 02 comes with detailed, teacher-verified solutions. We have provided step-by-step answers for Chemistry to help students of Class 7 understand correct methodology and marking scheme.
Practicing this Chemistry paper helps in time management and identifying important topics. For Class 7, solving mock papers is the best way to gain confidence and reduce exam-day anxiety.
Yes, all our study materials for Class 7 Chemistry are provided in a mobile-friendly PDF format. You can easily download ICSE Class 7 Chemistry Sample Paper with Solutions Set 02 on your mobile device.