Name the major components of LPG. Why is the leakage of LPG from a gas cylinder detected easily although the gas itself is colorless?

A major component of gobar gas is:

Name the major gas present in exhaled air and inhaled air?

The gas we use in the kitchen is called liquified petroleum gas (LPG). In the cylinder it exist as a liquid. When it comes out from the cylinder it becomes a gas (Change-A) then it burns (Change-B). The following statements pertain to these changes. Choose the correct one.

Gurmeet's mother uses cylinder to cook chapatti on gas burner at home. Name the gas in cylinder.

When zinc metal is treated with a dilute solution of a strong acid, a gas is evolved, which is utilised in the hydrogenation of oil. Name the gas evolved. Write the chemical equation of the reaction involved and also write a test to detect the gas formed.