Question

Synthetic petrol is prepared by using a mixture of:
A.Coal gas \[ + {H_2}\] gas
B.Water gas \[ + {H_2}\] gas
C.Semi water gas
D.Carburetted water gas

Answer 1

Hint:The main component involved in production of synthetic petrol is syngas. So analyze the components of syngas briefly. Syngas is made by partial oxidation of oil, natural gases, coal and biomass. Further this syngas undergoes Fischer Tropsch synthesis to produce synthetic fuel.

Complete answer:
First let us see what synthetic fuel is. Synthetic fuel is something which is not obtained naturally from nature but rather is made by combining different renewable energy resources. It is also called synfuel. It is a liquid based fuel.
Synthetic petrol is mainly produced from syngas. Now syngas is a mixture of hydrogen and carbon monoxide. Synthetic petrol is mainly obtained from a process called Bergius process. In the Bergius process, hydrogen gas and coal are heated together which produces a mixture of hydrocarbons through the process of hydrogenation. The general reaction involved in this process is,
$nC + (n - x + 1){H_2} \to {C_n}{H_{2n - 2x + 2}}$ , where x is the degree of unsaturation.
The source of synthetic fuels can be any combustible carbon or hydrogen containing feedstock. Here we analyzed that synthetic fuel is obtained from syngas, a mixture of carbon monoxide which is coal gas and hydrogen gas.

So, option A is the correct answer.

Note:
In some places synthetic fuel can be used as a substitute in internal combustion engines. It can also be used as a blend with conventional fossil fuels. But synthetic fuel does have some harmful effects. Its burning can load the environment with carbon dioxide which is a major reason for the rise in temperature of the environment.
In today’s world it is a matter of severe discussion whether synthetic petrol can replace the existing crude oil or not because the existing fuels emit a huge number of harmful substances in the environment which have raised serious red flags for the quality of life of the upcoming generation.