Thermodynamics ...

What are the most favourable conditions for the reaction;
$${ SO }_{ 2 }(g)+\cfrac { 1 }{ 2 } { O }_{ 2 }(g)\leftrightharpoons { SO }_{ 3 }(g);\Delta { H }^{ o }=-ve$$ to occur?

Given, 

If $$\Delta H_{f}(H_{2}O)$$ is $$-285.20\ kJ\ mol^{-1}$$, then $$\Delta H_{f}^{\circ}(OH^{-})$$ is:

The enthalpy of combustion for the $$H_{2}$$, cyclohexene and cyclohexane are $$-241, -3800$$ and $$-3920kJ\ mol^{-1}$$, respectively. Heat of hydrogenation of cyclohexene is:

Standard heats of formation for $$C{Cl}_{4},{H}_{2}O,{CO}_{2}$$ and $$HCl$$ at $$298K$$ are $$-25.5,-57.8,-94.1$$ and $$-22.1kJ/mol$$ respectively.
For the reaction, what will be $$\Delta H$$?
$$C{Cl}_{4}+2{H}_{2}O\rightarrow {CO}_{2}+4HCl$$

Water is brought to boil under the pressure of $$1.0\ atm$$. When an electric current of $$0.50\ A$$ from a $$12\ V$$ supply is passed for $$300\ s$$ through resistance in thermal contact with it is found that $$0.798\ g$$ of water is vapourised. Calculate the molar internal energy change at boiling point $$(373.15\ K)$$.

Given: $$S+\dfrac { 3 }{ 2 } { O }_{ 2 }\longrightarrow S{ O }_{ 3 }+2x$$ $$kcal$$
           $$S{ O }_{ 2 }+\dfrac { 1 }{ 2 } { O }_{ 2 }\longrightarrow S{ O }_{ 3 }+y$$ $$kcal$$

A particular reaction at $${27}^{o}C$$ for which $$\Delta H > 0$$ and $$\Delta S> 0$$ is found to be non-spontaneous. The reaction may proceed spontaneously if:

Although the dissolution of ammonium chloride in water is an endothermic reaction, even then it is spontaneous because:

The enthalpy of hydrogenation of benzene is $$-49.8\ kcal/mol$$ while its resonance energy is $$36.0\ kcal/mol$$. The enthalpy of formation of benzene is: