What happens during a spontaneous process?

For the reaction $PCl_5 \to PCl_3 + Cl_2$,$\Delta H = 75 \ kJ \ mol^{-1}$ and $\Delta S = 120 \ J \ K^{-1} \ mol^{-1}$. At which temperature will the reaction be spontaneous? (in $K$)

For a reaction $\Delta H = 9.08 \ kJ \ mol^{-1}$ and $\Delta S = 35.7 \ J \ K^{-1} \ mol^{-1}$. Which of the following statements is correct for the reaction?

Calculate the work done in Joules $(J)$ when $50 \ g$ of iron is dissolved in $HCl$ in an open beaker at $25 \ ^oC$. The atmospheric pressure is $1 \ atm$.

Based on the provided table, which of the following options correctly identifies the spontaneous reactions?

	$\Delta_r H^{\circ}$	$\Delta_r S^{\circ}$	$\Delta_r G^{\circ}$	Spontaneity of the reaction
$A$	$+$	$+$	$+$	Spontaneous at low $T$
$B$	$+$	$+$	$-$	Spontaneous at high $T$
$C$	$-$	$-$	$-$	Spontaneous at low $T$
$D$	$+$	$-$	$+$	Spontaneous at high $T$

The temperature in $K$ at which $\Delta G = 0$, for a given reaction with $\Delta H = -20.5 \ kJ \ mol^{-1}$ and $\Delta S = -50.0 \ J \ K^{-1} \ mol^{-1}$ is: