the density of a gas relative to the density of hydrogen
The amount of mass of a vapour per unit volume of the vapour. The vapour density is expressed in grams per litre and is compared to the density of air, which is equal to 1.
The relative weight of a vapour compared to an equal volume of air (indicates whether vapours will rise or sink). If the vapour density of a substance is less than one, it will tend to rise in air; if the vapour density is greater than one, it will fall in air. Substances with high vapour densities will collect in the bottom of tanks
The weight of a vapour or gas compared to the weight of an equal volume of air. The vapour density of air is one. Gases with a vapour density greater than 1 are heavier than air and will settle near the ground and in low lying areas.
the density of a vapour compared to the density of an equal amount of air.