Question

One mole of oxygen is expanded from a volume 1 l to 5 l at a, constant temperature at=280k.the change in internal energy is

Answer 1

Answer:

The increment in the internal energy is

ΔU=∫V1V1(∂U∂V)TdV

But from second law

(∂U∂V)T=T(∂S∂V)T−p=T(∂p∂T)V−p

On the other hand p=RTV−b−aV2

or, T(∂T∂T)V=RTV−b and (∂U∂V)t=aV2

So, ΔU=a(1V1−1V2)

(b) From the first law

Q=A+ΔU=RT1nV2−bV1−b.