Search results
Results from the WOW.Com Content Network
Air is given a vapour density of one. For this use, air has a molecular weight of 28.97 atomic mass units, and all other gas and vapour molecular weights are divided by this number to derive their vapour density. [2] For example, acetone has a vapour density of 2 [3] in relation to air. That means acetone vapour is twice as heavy as air.
In biology, the unit "%" is sometimes (incorrectly) used to denote mass concentration, also called mass/volume percentage. A solution with 1 g of solute dissolved in a final volume of 100 mL of solution would be labeled as "1%" or "1% m/v" (mass/volume). This is incorrect because the unit "%" can only be used for dimensionless quantities.
In some cases (for instance, in the United States oil and gas industry), density is loosely defined as its weight per unit volume, [2] although this is scientifically inaccurate – this quantity is more specifically called specific weight. For a pure substance the density has the same numerical value as its mass concentration.
A United States Navy Aviation boatswain's mate tests the specific gravity of JP-5 fuel. Relative density, also called specific gravity, [1] [2] is a dimensionless quantity defined as the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material.
Specific volume is an example of an intensive property because it is the ratio of volume occupied by a unit of mass of a gas that is identical throughout a system at equilibrium. [17] 1000 atoms a gas occupy the same space as any other 1000 atoms for any given temperature and pressure.
Specific volume is inversely proportional to density. If the density of a substance doubles, its specific volume, as expressed in the same base units, is cut in half. If the density drops to 1/10 its former value, the specific volume, as expressed in the same base units, increases by a factor of 10.
In chemistry, the mass concentration ρ i (or γ i) is defined as the mass of a constituent m i divided by the volume of the mixture V. [1]= For a pure chemical the mass concentration equals its density (mass divided by volume); thus the mass concentration of a component in a mixture can be called the density of a component in a mixture.
Syngas, or synthesis gas, is a mixture of hydrogen and carbon monoxide, [1] in various ratios. The gas often contains some carbon dioxide and methane . It is principally used for producing ammonia or methanol .