Question

State the basic difference between a gas and a vapour.

Answer 1

-The vapour in its natural state is a solid or liquid at room temperature. However, a gas in its natural state at room temperature would still be a gas.

-Vapour is a substance which has experienced a phase change. Gas is a substance which has not, and will not experience a phase change.

-A gas is a substance above its critical temperature but below its critical pressure, while a vapour is a substance above its boiling point.

-Gas is one of the 4 states of matter whereas vapour does not classify as such. It is just a substance in gaseous form.

-Gas cannot be seen while vapours are visible.

-Vapours can turn back and form into solid and liquid states but a gas cannot.