Alkanes - Conceptual Questions

1. What are hydrocarbons and How do you classify hydrocarbons?
2. What are alkanes and why they are called paraffins?
3. What is the general formual of cycloalkanes?
4. What is the general formual of open chain and acyclic alkanes?
5. What is the IUPAC system of nomenclature of alkanes?
6. What is the IUPAC system of nomenclature of cycloalkanes?
7. Explain the concept of conformations in alkanes.
8. Explain the saw horse representation and Newman representation of alkanes.
9. Discuss the stability of various conformations of alkanes.
10. Explain the concept of conformations in cycloalkanes.

11. Explain the following methods of preparation of alkanes.
i. From unsaturated hydrocarbons
ii. from alkyl halides
a. Wurtz reaction
b. Reduction of alkyl halides – using zinc and HCl, using hydrogen in presence of platinum or palladium (catalytic hydrogenation), using hydrogen iodide in presence of red phosphrus, using zinc copper couple and alcohol.
c. By reaction with Grignard reagent
iii. from carboxylic acids
a. Decarboxylation reaction
b. Kolbe’s reaction

12. What are physical properties of amines?
a. Physical state and smell
b. Melting point
c. Boiling points
d. Solubility in water
e. Density

13. Chemical Properties of Alkanes

A. Substitution reactions of alkanes
i. Halogenation
ii. Nitration
iii. Sulphonation

B. Oxidation
i. Complete oxidation or combustion
ii. Incomplete combustion
iii. controlled oxidation

C. Action of steam

D. Isomerisation (Formation of branched alkanes)
E. Aromatization
F. Thermal decomposition or fragmentation