Enthalpy Questions

The standard heat of formation, in $\text{kcal/mol}$ of ${\text{Ba}}^{2+}$ is :[Given : standard heat of formation of ${\text{SO}}_4^{2-}(\text{aq})=-216\text{kcal/mol}$, standard heat of crystallisation of ${\text{BaSO}}_4(\text{s})=-4.5\text{kcal/mol}$, standard heat of formation of ${\text{BaSO}}_4(\text{s})=-349\text{kcal/mol}$ ]

Which of the following are not state functions?(I) $q+w$ (II) $q$ (III) $w$ (IV) $H-TS$

From the following bond energies: $\text{H-H}:431.37\text{kJ/mol}$ $\text{C=C}:606.10\text{kJ/mol}$ $\text{C-C}:336.49\text{kJ/mol}$ $\text{C-H}:410.50\text{kJ/mol}$ Enthalpy for the reaction will be:

A reaction having equal energies of activation for forward and reverse reactions has:

For the reaction ${\text{X}}_2{\text{O}}_4(l)\to 2{\text{XO}}_2(g)$, $\Delta U=2.1\text{k cal}$ and $\Delta S=20{\text{cal K}}^{-1}$ at $300\text{K}$. Hence, $\Delta G$ is: