The percentage of carbon(IV) oxide in air is

An example of a physical change is 

Boyle's law can be expressed mathematically as

What is the vapour density of 560cm\(^3\) of a gas that weighs 0.4g at s.t.p?

[Molar Volume of gas at s.t.p = 22.4 dm\(^3\) ]

When the subsidiary quantum numbers (l) equals 1, the shape of the orbital is