Question

Relationship between vapour density and molecular formula

Answer 1

Relative Molecular Mass

Relative molecular mass is the ratio of the mass of one molecule of a substance to the mass th of a carbon atom, or 1 amu.

Vapour Density

Vapour density is the ratio of the mass of a volume of a gas, to the mass of an equal volume of hydrogen, measured under the same conditions of temperature and pressure.

According to Avogadro's law, equal volumes of all gases contain equal number of molecules.

Answer 2

It may be defined as mass of 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.(and thus molar mass = ~ 2× vapour density). for example, vapour density of mixture NO2 and N2O4 is 38.
molecular mass :
Relative molecular mass is the ratio of the mass of one molecule of a substance to the mass of a carbon atom or , one amu ( one amu= 1.67 × 10 to the power of -18) ...