Question

Alkanes are used as fuel:
(A) because there is an evolution of a large amount of heat during combustion
(B) because there is an evolution of a large amount of heat during conduction
(C) because there is an evolution of a large amount of heat during neutralization
(D) because there is an evolution of a large amount of heat during combustion

Answer 1

Hint: Saturated hydrocarbons that contain only a single bond are called alkanes. These alkanes consist of hydrogen in every possible location, due to that alkanes are called saturated hydrocarbons. The general formula of alkanes is ${{C}_{n}}{{H}_{2n+2}}$

Complete step by step solution:
The first four alkanes are gases in nature which are named as methane, ethane, propane, and butane. In alkanes, every carbon attached with a single bond, the –ane suffix represents the carbon-carbon bond is single bond in parent chain of alkanes and the number of prefixes based indicates the number carbons in parent chain in alkanes as pent-, hex-, hept-, oct-, non-, dec-, etc.
The alkanes are used as the most important sources of natural gas and petroleum. All saturated hydrocarbons are extracted from the fractional distillation of petroleum. Depending on the number of carbons, the calorific value of alkanes changes which is used as fuel. Because there is a large amount of heat released during the combustion of alkanes.

Hence, the correct answer is option A.

Note: Highly combustible and used as fuels are the alkanes. During the combustion of alkanes form water and carbon dioxide. The first four carbons in alkanes are used as directly gaseous fuels. Alkanes from C-5 carbons to ${{C}_{17}}{{H}_{36}}$ are liquids. A mixture of alkanes from pentane to decane is gasoline. Alkanes with the higher value of carbon number found in diesel, jelly, tar, paraffin wax, etc.