For a reversible adiabatic expansion of an ideal gas,which of the following is equal to zero?

The enthalpy change for the transition of liquid water to steam is $37.3 \ kJ \ mol^{-1}$ at $373 \ K$. Find $\Delta S$ in $J \ mol^{-1} \ K^{-1}$.

For the reaction $2 H_{2(g)} + O_{2(g)} \longrightarrow 2 H_2O_{(g)}$,at $300 \ K$,$\Delta G$ and $\Delta H$ of water are $-228.4 \ kJ \ mol^{-1}$ and $-241.60 \ kJ \ mol^{-1}$,respectively. Calculate the value of change in entropy for the given reaction.

For a process to be spontaneous,the total entropy change of the system and its surroundings must be $ \Delta S_{total} > 0 $. This condition is characteristic of which type of process?

Given the standard entropy values at $298 \ K$ and $1 \ atm$ as $H_2(g) : 130.6 \ J \ K^{-1} \ mol^{-1}$,$Cl_2(g) : 223.0 \ J \ K^{-1} \ mol^{-1}$,and $HCl(g) : 186.7 \ J \ K^{-1} \ mol^{-1}$,calculate the entropy change $(\Delta S^{\circ})$ in $J \ K^{-1} \ mol^{-1}$ for the reaction: $H_2(g) + Cl_2(g) \rightarrow 2HCl(g)$

For the conversion $C$ (graphite) $\to C$ (diamond),the $\Delta S$ is: