Evaporation of water is

For the reaction,$A_{(s)} + 3B_{(g)} \to 4C_{(s)} + D_{(l)}$,$\Delta H$ and $\Delta U$ are related as $\dots$

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.

Which of the following is an extensive property?

Calculate work done in isothermal reversible expansion of $1 \ mol$ of an ideal gas from an initial pressure of $10 \ bar$ to a final pressure of $1 \ bar$ at $300 \ K$ $\left(R = 8.314 \ J \ K^{-1} \ mol^{-1}\right)$. (in $kJ$)

The difference between $C_p$ and $C_v$ can be derived using the empirical relation $H = U + PV$. Calculate the difference between $C_p$ and $C_v$ for $10$ moles of an ideal gas.