What is the difference between $\Delta H$ and $\Delta U$ for the combustion of methane at $25\,^oC$?

If standard molar enthalpy change and standard molar internal energy change measured in a bomb calorimeter are equal,which one of the following statements is correct?

The heat of neutralization of a strong acid and a strong alkali is $-57.0 \ kJ \ mol^{-1}$. The heat released when $0.5 \ mole$ of $HNO_3$ solution is mixed with $0.2 \ mole$ of $KOH$ is ....$kJ$

Which of the following is true for the reaction $H_2O_{(l)} \rightleftharpoons H_2O_{(g)}$ at $100 ^oC$ and $1 \text{atm}$ pressure?

For the reaction,$X_2O_{4(l)} \to 2XO_{2(g)}$,$\Delta U = 2.1 \ kcal$ and $\Delta S = 20 \ cal \ K^{-1}$ at $300 \ K$. Calculate $\Delta G$ in $kcal$.

$A$ gas expands from $3\, dm^3$ to $5.8\, dm^3$ against a constant external pressure of $3\, bar$. The work done during expansion is used to heat $2\, moles$ of water from $290\, K$ to a final temperature of $T\, K$. If the specific heat of water is $4.2\, J\, g^{-1}\, K^{-1}$,then $T = ......\, K$. (in $.6$)