Question

The density of air is 0.001293 $gm{l}^{-1}$ .It's vapour density is:

• A. 148
• B. 14.48
• C. 1.448
• D. 0.1448

Answer 1

The correct option is B 14.48

$\text{Molecular mass}=2\times \text{vapour density}$

Given density $=0.001293gm{l}^{-1}$

1 ml has 0.001293 gm.

$\therefore$22400 ml has $0.001293\times 22400gm$

$1mole=28.96gm$

Molecular mass of air $=28.96gm$

Vapour density $=\frac{Mol.mass}{2}=14.48$