Answer to Question #174212 in Physical Chemistry for Divyanshu

Question

Solid ammonium chloride undergoes sublimation on heating. In the vapour phase ammonium 

chloride decomposes to give NH3(g) and HCI(g). The following equilibrium is established. 

 NH4Cl(s) ⇌ NH3(g)+ HCl (g)

 What is the number of 

i) phases in the system, 

ii) components in the system, and 

 iii) degrees of freedom of the system?

Answer 1

1. Two phases, that is, solid and gaseous phases

2. Three components (NH4Cl, NH3 and HCl)

3. The system is disordered because gases are given out during the sublimation. (Gases move randomly, hence the molecules are very free)