Establish the relationship between vapour density and molecular mass of a gas by applying Avogadro’s law.

Open in App

Solution

As we know, Vapor density is defined as “mass of a certain volume of a gas divided by the mass of the same volume of hydrogen”.
Avogadro’s law which states that “At same temperature and pressure, equal volume of all gases will have the same number of molecules”.

$V . D . = \frac{M a s s o f 1 v o l u m e o f g a s o r v a p o u r}{M a s s o f 1 v o l u m e o f h y d r o g e n}$

Applying Avogadro’s law,

$V . D . = \frac{M a s s o f 1 m o l e c u l e o f g a s o r v a p o u r}{M a s s o f 1 m o l e c u l e o f h y d r o g e n}$

Since hydrogen is diatomic,

$V . D . = \frac{M a s s o f 1 m o l e c u l e o f g a s o r v a p o u r}{2 \times m a s s o f 1 a t o m o f h y d r o g e n}$

2 $\times$ V.D. = Relative molecular mass of gas or vapour

Therefore relative molecular mass = 2 $\times$ Vapour density

Suggest Corrections

Similar questions

Gas laws establish relationship between:

Vapour density of a gas is 22. Its molecular mass will be:

Vapour density of a gas is 22. What is its molecular mass

Join BYJU'S Learning Program