Total Marks: 65
Time Allowed: 2 Hours 20 Minutes
Section A: MCQs (12 Marks, 20 Minutes)
1. Which metal is extracted from bauxite?
a) Iron
b) Aluminum
c) Copper
d) Zinc
2. What is the general formula of alkenes?
a) CₙH₂ₙ₊₂
b) CₙH₂ₙ
c) CₙH₂ₙ₋₂
d) CₙH₂ₙ₊₁OH
3. What is the main component of natural gas?
a) Butane
b) Propane
c) Methane
d) Ethanol
4. What type of reaction occurs when hydrogen is added to an alkene?
a) Addition
b) Elimination
c) Substitution
d) Redox
5. Which of the following is an alloy?
a) Iron
b) Copper
c) Brass
d) Zinc
6. What is the function of limestone in the extraction of iron?
a) Oxidizing agent
b) Reducing agent
c) Slag formation
d) Catalysis
7. The functional group present in carboxylic acids is:
a) –OH
b) –CHO
c) –COOH
d) –COO–
8. What is the pH of pure water?
a) 5
b) 7
c) 9
d) 12
9. Which gas is produced when calcium carbonate reacts with hydrochloric acid?
a) Oxygen
b) Hydrogen
c) Carbon dioxide
d) Nitrogen
10. What happens when ethanol reacts with sodium?
a) Forms water
b) Forms sodium ethoxide and hydrogen gas
c) No reaction
d) Produces a strong acid
11. Which process is used to refine petroleum?
a) Fermentation
b) Distillation
c) Crystallization
d) Electrolysis
12. The formula of sodium carbonate is:
a) NaCl
b) Na₂CO₃
c) NaOH
d) NaHCO₃
Section B: Short Questions (33 Marks)
(Attempt any 11 questions, each question carries 3 marks.)
1. Define isomerism and give an example. OR Write the structural formula of two isomers of butane.
2. Write the balanced chemical equation for the reaction of ethene with hydrogen. OR Explain the reaction of ethene with bromine water.
3. What is meant by a saturated and unsaturated hydrocarbon? Give an example of each. OR What happens when methane is burned in excess oxygen? Write the equation.
4. Define electroplating and explain its purpose. OR Write the reaction for the electrolysis of copper sulfate using copper electrodes.
5. Describe the laboratory preparation of carbon dioxide. OR Write the reaction of carbon dioxide with sodium hydroxide.
6. Explain the process of polymerization. OR Write a reaction for the formation of polystyrene.
7. How does sulfur dioxide contribute to acid rain? OR Write a balanced reaction showing the formation of acid rain.
8. Define an acid and a base according to the Bronsted-Lowry concept. OR Write the balanced reaction for the neutralization of H₂SO₄ with NaOH.
9. How does aluminum react with hydrochloric acid? Write the equation. OR Explain why aluminum does not corrode easily.
10. What happens when calcium hydroxide reacts with carbon dioxide? Write the reaction. OR Write the balanced equation for the thermal decomposition of limestone.
11. What is fermentation? Write a chemical equation for the fermentation of glucose. OR What are detergents? How do they differ from soaps?
Section C: Long Questions (20 Marks, Each Question = 5 Marks)
(Attempt any 4 questions, each question carries 5 marks and is divided into three parts (a, b, c)
Q1.
a) Write the balanced equation for ammonia production using the Haber process. (2 marks)
b) What are the optimal conditions for the Haber process? (2 marks)
c) Why is ammonia used in fertilizers? (1 mark)
OR
a) Write the reaction involved in the Contact Process for sulfuric acid. (2 marks)
b) Why is sulfuric acid called the “king of chemicals”? (2 marks)
c) What happens when sulfuric acid reacts with sodium carbonate? (1 mark)
Q2.
a) Write the balanced equation for the reaction of ethanol with acetic acid. (2 marks)
b) What happens when ethene undergoes hydrogenation? Write the reaction. (2 marks)
c) What is the difference between alkanes and alkenes? (1 mark)
OR
a) Write the polymerization reaction for Teflon (PTFE). (2 marks)
b) What are biodegradable and non-biodegradable polymers? (2 marks)
c) Write the equation for the combustion of methane. (1 mark)
Q3.
a) Write the balanced reaction for the electrolysis of NaCl. (2 marks)
b) What are anodes and cathodes? (2 marks)
c) What happens when copper reacts with oxygen? (1 mark)
OR
a) How is aluminum extracted from bauxite? Write the equation. (2 marks)
b) Why is cryolite used in the extraction of aluminum? (2 marks)
c) Why does aluminum not corrode easily? (1 mark)
Q4.
a) Write the reaction showing the formation of ozone in the atmosphere. (2 marks)
b) How does the greenhouse effect contribute to climate change? (2 marks)
c) What are the effects of acid rain on buildings? (1 mark)
OR
a) Write the decomposition reaction of calcium carbonate in cement production. (2 marks)
b) How do CFCs damage the ozone layer? (2 marks)
c) What is the role of scrubbers in reducing air pollution? (1 mark)