In a certain `(2/5) th` of the energy of molecules is associated with the ratation of molecules and the rest of it is associated with the motion of the centre of mass.
(a) What is the average translational energy of one such molecule when the temperature id `27^@ C` ?
(b) How much energy must be supplied to one mole of thsi gas constant volume to raise the temperature by `1^@ C` ?

Answer

A, B

Explanation

(a) Average translational kinetic energy of any type of molecules is
`3/2 k T = 3/2 (1.38 xx 10^-23)(300)`
= `6.21 xx 10^-21 J`.
(b) `2/5` energy is associated with rotation. Hence, it is diatomic gas.
`Q = n C_V Delta T = (1) (5/2R)(1)`
= `5/3 xx 8.31 = 20.8 J`.