ICSE MCQs Chemistry Ammonia - Study of Compounds

ICSE Chemistry MCQs

ICSE Chemistry – Ammonia

1. What is the molecular formula of ammonia?

A) NH₄

B) NH₃

C) N₂H₄

D) NO₃

Answer: B) NH₃

2. Ammonia is a:

A) Colourless gas with a pungent smell

B) Yellow gas with a sweet smell

C) Blue liquid

D) Colourless liquid with no smell

Answer: A) Colourless gas with a pungent smell

3. Ammonia is highly soluble in:

A) Kerosene

B) Water

C) Benzene

D) Carbon tetrachloride

Answer: B) Water

4. The laboratory preparation of ammonia involves heating:

A) Sodium chloride with sulphuric acid

B) Ammonium chloride with calcium hydroxide

C) Ammonium nitrate with water

D) Nitrogen with hydrogen

Answer: B) Ammonium chloride with calcium hydroxide

5. The drying agent commonly used for ammonia is:

A) Concentrated H₂SO₄

B) Anhydrous CaCl₂

C) Quicklime (CaO)

D) P₂O₅

Answer: C) Quicklime (CaO)

6. Ammonia cannot be dried using concentrated sulphuric acid because it:

A) Is insoluble in H₂SO₄

B) Reacts with H₂SO₄

C) Decomposes H₂SO₄

D) Evaporates H₂SO₄

Answer: B) Reacts with H₂SO₄

7. The gas collected in the laboratory preparation of ammonia is collected by:

A) Downward displacement of water

B) Upward displacement of air

C) Downward displacement of air

D) Over mercury

Answer: C) Downward displacement of air

8. Ammonia is lighter than:

A) Hydrogen

B) Oxygen

C) Helium

D) Nitrogen

Answer: B) Oxygen

9. Ammonia turns moist red litmus paper:

A) Blue

B) Green

C) Yellow

D) White

Answer: A) Blue

10. The aqueous solution of ammonia is commonly called:

A) Ammonium hydroxide

B) Ammonium chloride

C) Ammonium nitrate

D) Ammonium sulphate

Answer: A) Ammonium hydroxide

11. Ammonia reacts with hydrogen chloride gas to form:

A) NH₄OH

B) NH₄Cl

C) N₂

D) H₂

Answer: B) NH₄Cl

12. The reaction between NH₃ and HCl produces:

A) Brown fumes

B) White fumes

C) Green fumes

D) No visible change

Answer: B) White fumes

13. Ammonia is a:

A) Strong acid

B) Weak acid

C) Strong alkali

D) Weak alkali

Answer: D) Weak alkali

14. The catalyst used in the Haber process is mainly:

A) Copper

B) Iron

C) Nickel

D) Platinum

Answer: B) Iron

15. The Haber process is used for the manufacture of:

A) Nitric acid

B) Ammonia

C) Sulphuric acid

D) Hydrochloric acid

Answer: B) Ammonia

16. The reactants used in the Haber process are:

A) Nitrogen and oxygen

B) Nitrogen and hydrogen

C) Hydrogen and oxygen

D) Nitrogen and chlorine

Answer: B) Nitrogen and hydrogen

17. The balanced equation for the Haber process is:

A) N₂ + H₂ → NH₃

B) N₂ + 2H₂ → 2NH₃

C) N₂ + 3H₂ ⇌ 2NH₃

D) 2N₂ + H₂ ⇌ 2NH₃

Answer: C) N₂ + 3H₂ ⇌ 2NH₃

18. In the Haber process, increasing pressure favours the formation of:

A) Nitrogen

B) Hydrogen

C) Ammonia

D) Oxygen

Answer: C) Ammonia

19. Ammonia reacts with oxygen in the presence of platinum to form:

A) Nitrogen dioxide directly

B) Nitric oxide and water

C) Nitrogen and water

D) Nitric acid directly

Answer: B) Nitric oxide and water

20. The oxidation of ammonia in the Ostwald process is carried out using:

A) Copper catalyst

B) Iron catalyst

C) Platinum catalyst

D) Zinc catalyst

Answer: C) Platinum catalyst

21. Ammonia can reduce heated metal oxides such as:

A) CuO

B) Na₂O

C) K₂O

D) CaO

Answer: A) CuO

22. When ammonia reacts with copper(II) oxide on heating, the black CuO changes to:

A) Green copper carbonate

B) Reddish-brown copper

C) Blue copper sulphate

D) White copper chloride

Answer: B) Reddish-brown copper

23. Ammonia is used in the manufacture of:

A) Fertilisers

B) Glass only

C) Cement only

D) Sodium chloride

Answer: A) Fertilisers

24. Which property of ammonia makes it suitable for fountain experiment?

A) It is highly soluble in water

B) It is heavier than water

C) It is insoluble in water

D) It is a liquid at room temperature

Answer: A) It is highly soluble in water

25. Which of the following is NOT a property of ammonia?

A) It has a pungent smell

B) It is highly soluble in water

C) It is a basic gas

D) It is heavier than air

Answer: D) It is heavier than air

Icse chemistry class 10 worksheet

Icse chemistry class 10 worksheet- Study of Compounds 

1. PERIODIC PROPERTIES

1. Explain why atomic radius generally decreases from left to right across a period.

2. Arrange Na, Mg, Al and Si in increasing order of atomic radius. Explain your answer.

Case Study Question

A student compares four Period 3 elements: Na, Mg, Al and Cl. The atomic size becomes progressively smaller across the period.

(a) What causes the decrease in atomic size?

(b) Which of the four has the highest electronegativity?

(c) Which would form the largest positive ion?

(d) State the general trend of first ionisation energy across a period.

2. CHEMICAL BONDING

1. Using electron-dot structures, explain the formation of magnesium chloride, MgCl₂.

2. Differentiate between an electrovalent bond and a covalent bond with respect to formation and electrical conductivity.

Case Study Question

Compound X has a high melting point and conducts electricity when molten but not when solid. Compound Y has a low melting point and does not conduct electricity in either state.

(a) Identify the likely type of bonding in X and Y.

(b) Explain the electrical conductivity of X.

(c) Give one example of Y.

(d) State why X is brittle.

3. ELECTROLYSIS

1. Describe the electrolysis of molten lead(II) bromide and write the half-equations at both electrodes.

2. Explain the principle of electroplating. Describe how an iron article can be coated with copper.

Case Study Question

A student electrolyses aqueous copper(II) sulphate using copper electrodes.

(a) Which electrode gains mass?

(b) Which electrode loses mass?

(c) Write the cathode half-equation.

(d) Explain why the concentration of CuSO₄ solution remains approximately unchanged.

4. METALLURGY

1. Explain the functions of coke, limestone and hot air in the extraction of iron in a blast furnace.

2. Differentiate between roasting and calcination. Give one chemical equation for each process.

Case Study Question

An ore contains iron(III) oxide mixed with earthy impurities. In a blast furnace, coke and limestone are added.

(a) What is the function of coke?

(b) What is the function of limestone?

(c) What is slag?

(d) Write the equation for the reduction of Fe₂O₃ by CO.

5. HYDROGEN CHLORIDE

1. Describe the laboratory preparation of hydrogen chloride gas from sodium chloride. Write the balanced equation.

2. Explain why hydrogen chloride gas shows acidic properties only in the presence of moisture.

Case Study Question

A jar containing dry HCl gas is connected to a fountain apparatus and water is introduced.

(a) What happens to the water level?

(b) Why is HCl highly soluble in water?

(c) What happens to moist blue litmus?

(d) Write the reaction between HCl and NH₃.

6. NITRIC ACID

1. Describe the oxidising action of concentrated nitric acid on copper. Write the balanced equation and identify the gas evolved.

2. What is aqua regia? State its composition and one important use.

Case Study Question

Copper reacts with concentrated nitric acid and produces a blue solution with brown fumes.

(a) Identify the brown gas.

(b) Why is the solution blue?

(c) Is nitric acid acting as an oxidising agent? Explain.

(d) Write the balanced equation.

7. SULPHURIC ACID

1. Describe the Contact Process for the manufacture of sulphuric acid, mentioning the catalyst and important conditions.

2. Explain the dehydrating action of concentrated sulphuric acid using sugar as an example.

Case Study Question

In a Contact Process plant, SO₂ is converted to SO₃ before the final absorption step.

(a) Name the catalyst.

(b) Write the reversible equation for SO₂ oxidation.

(c) Why is SO₃ not absorbed directly in water?

(d) Name the substance formed when SO₃ is absorbed in concentrated sulphuric acid.

8. ACIDS AND BASES

1. Distinguish between strong and weak acids in terms of ionisation in water. Give one example of each.

2. A solution has [H⁺] = 1 × 10⁻⁴ mol L⁻¹. Calculate its pH and state whether it is acidic or alkaline.

ICSE Class 10 Chemistry Chapter: Electrolysis test

ICSE Class 10 Chemistry

Chapter: Electrolysis

Time: 30 Minutes

Marks: 20

Question 1

(Answer all the questions)

i) Which of the following is a weak electrolyte?

a) Hydrochloric acid

b) Sodium chloride solution

c) Acetic acid

d) Molten sodium chloride

Ans: __________________

---

ii) During the electrolysis of molten lead bromide, the gas liberated at the anode is

a) Oxygen

b) Bromine vapours

c) Hydrogen

d) Chlorine

Ans: __________________

---

iii) An electrolyte conducts electricity due to the presence of _________.

a) Molecules

b) Free ions

c) Electrons only

d) Atoms

Ans: __________________

---

iv) Assertion: Copper is deposited at the cathode during the electrolysis of copper sulphate solution using copper electrodes.

Reason: Copper ions gain electrons at the cathode.

a) Assertion is True but Reason is False

b) Assertion is False but Reason is True

c) Both Assertion and Reason are True and Reason is the correct explanation

d) Both Assertion and Reason are True but Reason is not the correct explanation

Ans: __________________

---

v) Oxidation always takes place at the ________.

a) Cathode

b) Electrolyte

c) Anode

d) Battery

Ans: __________________

---

Question 2

Match the following

Column A	Column B
a) Electrolyte used in electroplating with silver	1) Cathode
b) Site of reduction	2) Silver nitrate solution
c) Non-electrolyte	3) Distilled water
d) Product formed at cathode during electrolysis of acidified water	4) Hydrogen gas
e) Electrode connected to the positive terminal	5) Anode

Answers

a) ________

b) ________

c) ________

d) ________

e) ________

---

Question 3

DURING the electrolysis of acidified water using platinum electrodes.

hydrogen ions move towards the cathode and hydroxide ions move towards the anode.

Answer the following questions.

a) Name the electrolyte used.

Ans: ______________________________

---

b) Which gas is evolved at the anode?

Ans: ______________________________

---

c) State one observation at the cathode.

Ans: ______________________________

---

d) Write the balanced equation for the cathode reaction.

Ans: ______________________________

---

e) Why is dilute sulphuric acid added to water before electrolysis?

Ans: ______________________________

---

Answer Key

Question 1

i) c) Acetic acid

ii) b) Bromine vapours

iii) b) Free ions

iv) c) Both Assertion and Reason are True and Reason is the correct explanation

v) c) Anode

---

Question 2

a → 2

b → 1

c → 3

d → 4

e → 5

---

Question 3

a) Acidified water (dilute sulphuric acid + water)

b) Oxygen gas

c) Bubbles of hydrogen gas are produced at the cathode.

d) 2H⁺ + 2e⁻ → H₂

e) To increase the electrical conductivity of water.

This paper closely follows the ICSE Class 10 format, difficulty level, and pattern of the sample you shared, while using different questions and a different case study.

Thermal decomposition of Lead nitrate video

🔥 Thermal Decomposition of Lead Nitrate (ICSE Chemistry) – Equation, Observation & Explanation

Icse chemistry practical chemistry video and observations 

 

🧪 Thermal Decomposition of Lead Nitrate 

The thermal decomposition of lead nitrate is one of the most important reactions in ICSE Chemistry. It is frequently asked in exams for equation writing, observations, and reasoning-based questions.

🔍 What is Thermal Decomposition?

Thermal decomposition is a chemical reaction in which a compound breaks down into simpler substances when heated. It is generally an endothermic reaction because heat is required to break chemical bonds.

⚗️ Thermal Decomposition of Lead Nitrate

When lead nitrate [Pb(NO₃)₂] is heated, it decomposes into:

Lead(II) oxide (PbO)

Nitrogen dioxide (NO₂)

Oxygen (O₂

✔ Heat (Δ) is required

✔ It is a decomposition reaction

2Pb(NO₃)₂ --> 2PbO + 4NO₂ + O₂

👀 Observations (Very Important for Exams)

When you perform this experiment, you will notice:

White crystals of lead nitrate turn into a yellow solid (PbO)

Reddish Brown fumes of nitrogen dioxide gas evolve

A colourless gas (oxygen) is released

👉 These observations are commonly asked in ICSE exams.

🧠 Explanation of the Reaction (summary )

When heated:
Lead nitrate absorbs heat energy
Chemical bonds break

New substances are formed:
PbO (yellow solid residue)
NO₂ (toxic reddish brown gas)
O₂ (supports combustion colourless gas)

⚠️ Safety Precautions

Perform in a well-ventilated area

Avoid inhaling NO₂ gas (toxic)

Use a test tube holder while heating

🎯 Why is This Reaction Important?

This reaction helps students understand:

Decomposition reactions

Effect of heat on compounds

Gas evolution and identification

Practical chemistry experiments

📚 ICSE Exam Questions (Practice)

1. Write the balanced equation for thermal decomposition of lead nitrate.

2. State two observations during the reaction.

3. Name the gases evolved.

4. Why is the reaction called thermal decomposition?

🧩 Key Points to Remember

✔ Reaction requires heat

✔ Reddish Brown fumes = NO₂

✔ Yellow residue = PbO

✔ Oxygen supports combustion

✔ Always write balanced equation

📌 Conclusion

The thermal decomposition of lead nitrate is a classic example of a decomposition reaction and an important concept in ICSE Chemistry. Understanding its equation, observations, and explanation will help you score full marks in exams.