9th class Chemistry, Chapter 11: Hydrocarbons MCQs

1. Which other atom is almost always present along with carbon atom in all organic compounds?

1. (A) Oxygen
2. (B) Nitrogen
3. (C) Hydrogen ✓
4. (D) Halogen

2. Which other metal can be used to reduce alkyl halides?

1. (A) Al
2. (B) Mg ✓
3. (C) Ni
4. (D) Co

3. If naphtha undergoes a combustion reaction what products do you expect it to form?

1. (A) Alkanes
2. (B) Alkenes
3. (C) CO₂ and H₂O ✓
4. (D) Both alkanes and alkenes

4. Why does a mixture of zinc and hydrochloric acid acts as a reducing agent?

1. (A) Because zinc acts as a reducing agent.
2. (B) Because atomic hydrogen is produced with Zn / HCl which acts as a reducing agent. ✓
3. (C) Because molecular hydrogen is produced with Zn / HCl which acts as a reducing agent.
4. (D) Because chloride ions are produced with Zn / HCl which act as a reducing agent.

5. Which alkane will evolve the most amount of heat when it is burnt with oxygen?

1. (A) Ethane
2. (B) Propane
3. (C) n-Butane ✓
4. (D) iso-Butane

6. Which reaction is not given by alkanes?

1. (A) Substitution
2. (B) Combustion
3. (C) Addition ✓
4. (D) Cracking

7. Which hydrocarbon is responsible for explosions in coal mines?

1. (A) Butane
2. (B) Pentane
3. (C) Methane ✓
4. (D) Ethene

8. Which product will be formed when ethyl bromide (CH₃CH₂Br) is treated with Zn/HCl?

1. (A) CH₄
2. (B) CH₃−CH₃ ✓
3. (C) CH₃−CH₂−CH₂−CH₃
4. (D) CH₃−CH₂−CH₃

9. Which of the following is not a process of halogenation of alkanes?

1. (A) Cracking ✓
2. (B) Chlorination
3. (C) Bromination
4. (D) Iodination

10. How many moles of oxygen will be required to completely burn propane?

1. (A) 4 moles
2. (B) 5 moles ✓
3. (C) 3 moles
4. (D) 6 moles

11. Organic chemistry is defined as the chemistry of:

1. (A) Carbon compounds ✓
2. (B) Hydrogen compounds
3. (C) Living things only
4. (D) Metals

12. Which of the following is classified as an inorganic compound?

1. (A) Calcium carbonate ✓
2. (B) Methane
3. (C) Glucose
4. (D) Ethane

13. The self-linking property of carbon is called:

1. (A) Isomerism
2. (B) Hydrogenation
3. (C) Catenation ✓
4. (D) Allotropy

14. Carbon generally forms:

1. (A) Metallic bonds
2. (B) Four covalent bonds ✓
3. (C) Ionic bonds
4. (D) Two covalent bonds

15. Compounds in which carbon forms single bonds with other atoms are called:

1. (A) Saturated compounds ✓
2. (B) Unsaturated compounds
3. (C) Aromatic compounds
4. (D) Ionic compounds

16. Hydrocarbons are compounds containing:

1. (A) Hydrogen and nitrogen
2. (B) Carbon and hydrogen only ✓
3. (C) Carbon, hydrogen and oxygen
4. (D) Carbon and oxygen

17. CNG stands for:

1. (A) Condensed Nitrogen Gas
2. (B) Cooking Natural Gas
3. (C) Compressed Natural Gas ✓
4. (D) Carbon Natural Gas

18. Methane is used to make:

1. (A) Glucose
2. (B) Carbon black and chloroform ✓
3. (C) Urea and ammonia
4. (D) Sulphuric acid

19. The general formula of alkanes is:

1. (A) CₙH₂ₙ
2. (B) CₙH₂ₙ₋₂
3. (C) CₙHₙ
4. (D) CₙH₂ₙ₊₂ ✓

20. Alkanes are also called:

1. (A) Saturated hydrocarbons ✓
2. (B) Unsaturated hydrocarbons
3. (C) Aromatic hydrocarbons
4. (D) Alkyl halides