Question

how does an adiabatic process differ from isothermal process. what happens to the internal energy of a gas during: 1)isothermal expansion 2)adiabatic expansion

Answer 1

In an adiabatic process, the rate of change of amount of heat is 0 i.e., dQ = 0 whereas in an isothermal process temperature remains constant i.e., dU = 0.
1) In an isothermal process internal energy does not change.
2)In an adiabatic process intrenal energy is equal to the negative of work done i.e., dU = -dW.