LPG stands for Liquefied Petroleum gas. It is a mixture of butane (C₄ H₁₀) and propane (C₃ H₈). They are stored in pressurized cylindrical vessels. This is because these gases liquefy under moderate pressure and vaporize on releasing the pressure. This property of LPG enable it to transport and store it in the liquid state, in which they are nearly 250 times as dense as they are when gases.

Sources of LPG: LPG can be obtained from the refining of crude oil or gas streams from grounds.

Properties: 1. It is a colorless gas.

2. It is an odorless gas so an odorant (ethanethiol) is added to detect its leakage.

3. It is heavier (1.5 times denser) than air.

4. It is non-toxic but can cause asphyxiation in very high concentrations in air.

Uses of LPG: 1. It is used as a cooking fuel.

2. It is used as an automobile fuel.

3. It is also used for lighting purpose.

Safety Precautions: 1. Always place the cylinder on a level surface.

2. Do not remove the regulator or appliance until the gas has been switched off.

3. Turn off the cylinder and open the windows if you smell leakage of gas.

4. Use soap water to detect the leakage. The water will bubble if there is leakage.