If the kinetic energy of the molecules in 5 litre of helium at 2 atm is `(E )`. What is the kinetic energy of molecules in 15 litre of oxygen at 3 atm in terms of `(E )` ?

Explanation

`pV = nRT`
`:. nRT = pV`
` U = f/2 (nRT) (f = degree of freedom)`
`:. U = f/2 (pV)`
or `U prop f p V`
(f) has become `5/3` times
become `3/2` times and (V) has become times
`:. (U)` will become `5/3 xx 3/2 xx 2 or 7.5` times.