Question

Is it possible to have gaseous dissociation without showing any abnormal vapor density?​

Answer 1

Answer:

Solution

Half of the vapour density of pure NH4Cl

The vapour density of fully dissociated NH4Cl would be half of the vapour density of pure NH4Cl

During thermal dissociation of gas, the vapour density decreases as the molecular weight also decreases.

NH4Cl→ NH3 + HCl

Molecular weight =2× vapour density.

The molecular weights of N4Cl, NH3 and HCl are 53.5 g/mol, 17 g/mol and 36.5 g/mol respectively. The average molecular weight of fully dissociated N4Cl will be 17+36.5÷2=26.75 g/mol which is one half of 53.5g/mol (the molecular weight of pure undissociated NH4Cl).