If the enthalpy of $B$ is greater than that of $A$,the reaction $A \to B$ is

The enthalpies of the elements in their standard states are assumed to be

What is the work done at $300 \ K$ for the reaction?
$SO_{2(g)} + \frac{1}{2} O_{2(g)} \rightarrow SO_{3(g)}$ (in $J$)?
(Given $R = 8.314 \ J \ K^{-1} \ mol^{-1}$)

$A$ given mass of gas expands from state $A$ to state $B$ by three paths $1, 2$ and $3$ as shown in the figure. If $w_1, w_2$ and $w_3$ are the work done by the gas along the three paths respectively,then:

$A$ system goes from $A$ to $B$ via two processes $I$ and $II$ as shown in the figure. If $\Delta U_1$ and $\Delta U_2$ are the changes in internal energies in the processes $I$ and $II$ respectively,then:

Identify the correct equation relating enthalpy $(H)$ and internal energy $(E)$.