Give reasons for the following in one or two sentences.
(`a`) A bottle of liquor ammonia should be cooled before opening the stopper.
(`b`) Equal volumes of gases contain equal number of moles.

Explanation

(`a`) When the bottle of liquor ammonia is cooled, the pressure inside decreases , and there are less chances of bumping when it is opened.
(`b`) `PV=nRT`
If pressure and temperature are the same for the two gases, the volume occupied is direct,y proportional to the number of moles. If volume is also same, the number of moles must be equal.