Which of the following relations is correct for an adiabatic process?

Predict the change in internal energy for an isolated system at constant volume.

Which among the following is $\text{NOT}$ an extensive property?

The heat of reaction at constant pressure is given by

One mole of an ideal gas at $300 \ K$ is expanded isothermally from an initial volume of $1 \ L$ to $10 \ L$. The change in internal energy for this process is ....... $cal$ $(R = 2 \ cal \ mol^{-1} \ K^{-1})$

Prove that the change in enthalpy of a system in which a chemical reaction occurs is equal to the heat gained by the system at constant pressure.