Moisture Moisture Moisture is the presence of a liquid, especially water, often in trace amounts. Small amounts of water may be found, for example, in the air (humidity), in foods, and in various commercial products. Moisture also refers to the amount of water vapour present in the air. Control of moisture in products can be a vital part of the process of the product. There is a substantial amount of moisture in what seems to be dry matter. Ranging in products from cornflake cereals to washing powders, moisture can play an important role in the final quality of the product. There
Vapour density Vapour density Vapour density is the density of a vapour in relation to that of hydrogen. It may be defined as mass of a certain volume of a substance divided by mass of same volume of hydrogen. vapour density = mass of "n" molecules of gas / mass of "n" molecules of hydrogen. Thus: vapour density = molar mass of gas / molar mass of H vapour density = molar mass of gas / 2.016 vapour density = ~½ × molar mass For example, vapour density of mixture of NO and NO is 38. 3.Vapour density is a unitless quantity.