Oxygen, nitrogn and helium gas are kept in three identical adiabatic constaners `P, Q` and `R` respectively at equal pressure. When the gases are pushed to half their original volumes. (initial temperature is same)

Options

A. The final temperature in the three containers will be the same.
B. The final pressures in the three containers will be the same.
C. The pressure of oxygen and nitrogen will be the same but that of helium will be different.
D. The temperature of oxygen and nitrogen will be the same but that of helium will be different

Answer

C, D

Explanation

`DeltaU = 0` (Adiabatic)
`U = const`
`nC_(v)T = const`
As `O_(2)` and `N_(2)` are diatomic, so there temp are equal but is different from He
For a adiabatic `PV^(gamma) =const`
For `O_(2),N_(2)` value of `gamma` is same `:.` pressure of `O_(2),N_(2)` remains same but different form He