Question

The vapour density of gas A is four times that of B. If molecular mass of B is M, then molecular mass of A is
a)M
b)4M
c)M/4
d)2M

Answer 1

Answer: b) 4M

Explanation:

Molar mass is twice of that of vapor density.

Molar mass = 2 × vapor density

Given: Vapor density of gas B= v

Molar mass of B = 2 × vapor density = 2v = M

Vapor density of gas A=$4\times {\text{Vapor density of B}=4\times v$

Molar mass of A = 2 × vapor density of gas A =$2\times 4v=8v$

If 2 v = M

Then 8v=$\frac{M}{2v}\times 8v=4M$

Thus molecular mass of A is 4M.

Answer 2

Explanation:

Here

V.D= Vapour density

M.mass = Molecular mass

A and B are gasses

M is the mplecular mass of Gass B

Thanks!