Gases are cooled in Joule-Thomson expansion, when it is __________ inversion temperature.

A. Below

B. At

C. Above

D. Either B or C

Answer: Option A

Solution(By Examveda Team)

Above the inversion temperature joule-thomson coefficient $${\left( {\frac{{\partial T}}{{\partial P}}} \right)_H} = - ve$$
So, by throttling (decreasing the pressure) the temperature increases and hence heating.
Below the inversion temperature houle-thomson coefficient $${\left( {\frac{{\partial T}}{{\partial P}}} \right)_H} = + ve$$
So,by throttling the temperature decreases hence cooling.