Page 20 - 10-Chem-12 Hydrocarbon

12. Hydrocarbon eLearn.Punjab

Short Questions

1. Differentiate between saturated and unsaturated hydrocarbons.

2. A compound consisting of four carbon atoms has a triple bond in it. How many hydrogen

atoms are present in it?

3. Why are the alkanes called ‘paraffins’?

4. What do you know about hydrogenation of alkenes?

5. How are alkyl halides reduced?

6. Why are the alkanes used as fuel?

7. How can you prepare ethene from alcohol and ethyl bromide?

8. Identify propane from propene with a chemical test.

9. Why are the alkenes called ‘olefins’?

10. Why alkane can’t be oxidized with KMnO4 solution?
11. What are the addition reactions? Explain with an example.

12. Justify that alkanes give substitution reactions.

13. Both alkenes and alkynes are unsaturated hydrocarbons. State the one most significant

difference between them.

14. Write the molecular, dot and cross and structural formula of ethyne.

15. Why are hydrocarbons soluble in organic solvents?

16. Give the physical properties of alkanes.

17. How can you identify ethane from ethene?

18. Why colour of bromine water discharges on addition of ethene in it?

19. State one important use of each:

(i) Ethene (ii) Acetylene

(iii) Chloroform (iv) Carbon tetrachloride

Extensive Questions:
1. What type of reactions are given by alkanes? Explain with reference to halogenations of

alkanes.
2. Alkanes are a source of heat. Explain it.
3. Prepare the following as directed:

(i) ethane from ethene;
(ii) acetylene from tetrahalide;
(iii) carbon tetracholride from methane;
(iv) ethylene glycol from ethene;
(v) 1,2-dibromoethane from ethene and
(vi) glyoxal from acetylene

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