CCl₄ (Carbon tetrachloride), CS₂ (Carbon disulfide), and Ether are volatile liquids . In a closed system or during measurement, they exist in equilibrium with their vapours. The addition of water vapour would mix with these vapours (according to Dalton's Law of partial pressures), thereby changing the density of the vapour phase mixture. Coke is a solid form of carbon and is non-volatile. The density of a solid is an intensive property and remains unaffected by the presence of water vapour in the surrounding environment.