Question

The vapour density of completely dissociated $\mathrm { NH } _ { 4 } \mathrm { Cl }$ would be.

• A. Slight less than half that of $\mathrm { NH } _ { 4 } \mathrm { Cl }$
• B. Half that of $\mathrm { NH } _ { 4 } \mathrm { Cl }$
• C. Double that of $\mathrm { NH } _ { 4 } \mathrm { Cl }$
• D. Determined by the amount of solid $\mathrm { NH } _ { 4 } \mathrm { Cl }$ in the experiment

Answer 1

Answer: (B)

Half that of $\mathrm { NH } _ { 4 } \mathrm { Cl }$

Answer 2

$\frac { \text { Normal molecular weight } } { \text { experiment al molecular wt. } }$= 1 + α

$\mathrm { NH } _ { 4 } \mathrm { Cl }$ ⇌ $\mathrm { NH } _ { 3 } + \mathrm { HCl }$

$\because \alpha = 1$ ∴Experimental Molecular wt = $\frac { \text { nor.mol.wt. } } { 2 }$