$A$ spontaneous process is impossible if ........

$A$ chemical reaction cannot occur at all if

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 an endothermic reaction at constant temperature $T$ and pressure $P$,if the process is spontaneous,which of the following is true?

The relation $\Delta G = \Delta H - T\Delta S$ was given by

An ideal gas expands from an initial volume of $5 \text{ dm}^3$ to $15 \text{ dm}^3$ against a constant external pressure of $2 \text{ atm}$. What is the work done by the gas (in $\text{ J}$)?