Question

The vapor pressures (in torr) of solid and liquid chlorine are given by ln ( P s ) = 24.320 − 3777 K T ln ( P l ) = 17.892 − 2669 K T where T is the absolute temperature. Calculate the temperature and pressure at the triple point of chlorine.

Answer 1

`T=172.37\ K`

`P_s=11.1095\ Pa`

Step-by-step explanation:

Triple point is that temperature and pressure for a substance at which the chemical substance coexists in liquid, solid and gaseous state with mutual equilibrium.

• At this point the equilibrium vapor pressure of solid, liquid and gas phases are mutually equal.

Given expressions of vapor pressure:

`ln (P_s)=24.320 -(3777  K)/(T)` ........................................(1)

`ln (P_l)=17.892 -(2669 K)/(T)` ..........................................(2)

Equating the vapor pressure of two phases of chlorine:

`24.320 -(3777  K)/(T)=17.892 -(2669 K)/(T)`

`T=172.37\ K`

The vapor pressure at this temperature:

`ln (P_s)=24.320 -(3777 )/(172.37)`

`P_s=11.1095\ Pa`