Question

Why do we use "work = − PΔV" for isothermal process instead of "work = − nRΔT"?

Answer 1

In isothermal process,, change in temperature is zero. i.e. zero workdone

so to that we use first formula for answer instead of zero

Answer 2

Hey Mate Ur Answer Is Here

we use "work = − PΔV" for isothermal

because in isothermal process temperature remains constant then volume changes with respect to pressure ... so we use W= p∆v