Question

vapour density of volatile substance is 4 in comparison to methane (CH₄ = 1) .Its molecular mass will be.

Answer 1

Dear student!

Vapor density is related with molecular mass as:

Molar mass = 2 x V.D

Now, in methane CH₄ , molar mass = 16,

So, Vapor density = 16/2 = 8

Here, relative vapor density is 4 for the substance i.e. four times the methane = 8x4 = 32

Hence, Molar mass of the substance = 2 x32 = 64