For a reaction,$\Delta H = +3 \, kJ$ and $\Delta S = +10 \, J/K$. At what minimum temperature (in $K$) will the reaction become spontaneous?

Values of $\Delta H$ and $\Delta S$ for five different reactions are given below. On the basis of these values,predict which one of these will be spontaneous at all temperatures.

Reaction	$\Delta H \ (kJ \ mol^{-1}) / \Delta S \ (J \ K^{-1} \ mol^{-1})$
$I$	$+98.0, +14.8$
$II$	$-55.5, -84.6$
$III$	$+28.3, -17.0$
$IV$	$-40.5, +24.6$
$V$	$+34.7, 0.0$

The entropy and enthalpy changes for the reaction $CO_{(g)} + H_2O_{(g)} \rightleftharpoons CO_{2(g)} + H_{2(g)}$ at $300 \ K$ and $1 \ atm$ are respectively $-42.4 \ J \ K^{-1}$ and $-41.2 \ kJ$. The temperature at which the reaction will go in the reverse direction is (in $K$)

Calculate the amount of work done during isothermal expansion of a gas from a volume of $4 \ dm^{3}$ to $6 \ dm^{3}$ against a constant external pressure of $3 \ atm$ (in $J$)?

What happens during a spontaneous process?

The standard enthalpy of the decomposition of $N_2O_4$ to $NO_2$ is $58.04 \, kJ$ and standard entropy of this reaction is $176.7 \, J/K$. The standard free energy change for this reaction at $25 \, ^oC$ is $..... \, kJ$