Question

What is the composition of liquefied petroleum gas(LPG)?

Answer 1

Hint: The main source of obtaining LPG is from the process of extracting natural gas from reservoirs. The primary constituents are thus, organic compounds.

Complete Step by Step Solution
The primary components of liquefied petroleum gas (LPG) are propane, butane, propylene, butylene, and isobutane. LPG is a highly flammable mixture of these hydrocarbon gases which is widely used as a fuel in household cooking applications. It is also used as a fuel in some automobiles.
Propane is a hydrocarbon with the chemical formula $ {{\text{C}}_{\text{3}}}{{\text{H}}_{\text{8}}} $ . It is one of the primary components of liquefied petroleum gas. This organic compound is known to exist in the gaseous phase under standard conditions for temperature and pressure (STP). However, propane can be compressed into a liquid if a sufficient amount of pressure is applied. It can be noted that propane is usually produced as a by-product during the refining of petroleum and the processing of natural gas.
Butane is an organic compound with the chemical formula $ {{\text{C}}_4}{{\text{H}}_{10}} $ . This hydrocarbon is one of the flammable compounds used in LPG. Butane, under standard conditions for temperature and pressure, exists as a colourless gas having a smell similar to that of natural gas or gasoline. However, butane can be compressed into a liquid for relatively easy transportation. The two structural isomers of butane are n-butane and isobutane. The former features a four-membered straight chain of carbon atoms whereas the latter features a branched structure. It can be noted that isobutane is also known as methylpropane.
Isobutane, also known as 2-methylpropane, is an organic compound with the chemical formula $ CH(CH_3)_3 $ . This compound is a structural isomer of butane and is one of the components of LPG. It is important to note that the melting and boiling points of butane and isobutane are not the same. The melting point of isobutane is equal to $ - 159.42 $ degrees Celsius and the boiling point of this isomer of butane is $ - 11.7 $ degrees celsius. It can also be noted that isobutane is often used as a propellant in aerosol cans.
Propylene, also known as propene, is an organic compound with the chemical formula $ {{\text{C}}_3}{{\text{H}}_6} $ . This unsaturated hydrocarbon contains one carbon-carbon double bond. It is often employed as a component of LPG.
Butylene, also known as butene, is an organic chemical compound whose chemical formula is $ {{\text{C}}_4}{{\text{H}}_8} $ . Butene is known to have many isomers since the double bond can be present at multiple points in the four-membered parent carbon chain. The most prominent isomers of butylene are 1-butylene, 2-butylene, and isobutylene.

Note
LPG has various uses such as heating and cooking in homes. LPG also has industrial and agricultural uses. It produces relatively large amounts of carbon dioxide, a greenhouse gas.It is highly flammable as it is much heavier than air.
CNG, an abbreviation of “Compressed Natural Gas” is primarily made up of Methane while LPG is primarily made up of propane.