For a certain reaction, $\Delta H^{\circ} = 40 \text{ kJ}$ and $\Delta S^{\circ} = 80 \text{ JK}^{-1}$. Find the temperature at which $\Delta G^{\circ} = 0$. (in $\text{ K}$)

For the conversion of limestone to lime,$CaCO_{3(s)} \rightarrow CaO_{(s)} + CO_{2(g)}$,the values of $\Delta H^{\circ}$ and $\Delta S^{\circ}$ at $298 \, K$ and $1 \, bar$ pressure are $+179.1 \, kJ \, mol^{-1}$ and $160.2 \, J \, K^{-1} \, mol^{-1}$ respectively. Assuming $\Delta H^{\circ}$ and $\Delta S^{\circ}$ do not change with temperature,at what temperature (in $K$) will the conversion of limestone to lime become spontaneous (in $, K$)?

Identify from the following the correct set of thermodynamic conditions for the reaction to be non-spontaneous at all temperatures.

For a certain reaction,$\Delta H = -210 \ kJ$ and $\Delta S = -150 \ J \ K^{-1}$. Find the temperature so that $\Delta G = 0$. (in $K$)

$\Delta G$ is net energy available to do useful work and is thus a measure of "free energy". Show mathematically that $\Delta G$ is a measure of free energy. Find the unit of $\Delta G$. If a reaction has positive enthalpy change and positive entropy change,under what condition will the reaction be spontaneous?

Calculate the work done (in $J$) when $4.5 \ g$ of $H_2O_2$ reacts against a pressure of $1.0 \ atm$ at $25 \ ^oC$. [$2H_2O_{2(l)} \to O_{2(g)} + 2H_2O_{(l)}$]