Question

What is the main constituent of LPG?

A) Methane

B) Butane

C) Propane

D) Both B and C

Answer 1

Hint: The main constituent of LPG is a hydrocarbon that contains three or four carbon atoms. Hydrocarbons are organic compounds that contain hydrogen and carbon as its main constituents.

Complete step-by-step solution:

The main constituents of LPG are butane and propane. Both of them are mixed to form LPG. So, option D is the correct one. Let us know more about LPG in detail.

(1). The full form of LPG is Liquefied Petroleum Gas. Though it mainly contains propane and butane, some traces of other hydrocarbons may be present in it. The chemical formula of propane is ${ CH }_{ 3 }{ CH }_{ 2 }{ CH }_{ 3 }$ and that of butane is ${ CH }_{ 3 }{ CH }_{ 2 }{ { CH }_{ 2 }CH }_{ 3 }$.

(2). It is a fossil-fuel, i.e. its main source is fossils. It is a non-renewable source of energy like all fossil fuels. A non-renewable energy source extinguishes after a certain period. LPG is extracted from natural gas and crude oil.

(3). The energy content in LPG is quite similar to petroleum. It burns very readily in the air giving out heat energy that is twice the energy given out by natural gas. This feature makes it an excellent fuel for cooking and heating purposes.

(4). This gas is called “liquefied” because it is normally stored under pressure in liquid form in containers like cylinders or tanks. The propane and butane in the LPG mix are in the gaseous phase under normal circumstances but they turn to liquid when pressure is applied. On the release of pressure, they turn into a gas again.

Therefore, the correct option is (D).

Note: Don’t confuse LPG with petrol. Petrol is available naturally in the liquid phase while LPG under normal pressure is available in the gaseous phase. LPG is more environmentally friendly compared to petroleum. Don’t confuse them.