If $900 \ J/g$ of heat is exchanged at the boiling point of water,what is the increase in entropy in $J \ K^{-1} \ mol^{-1}$?

Calculate the entropy change in $J \, mol^{-1} K^{-1}$ for the isothermal reversible expansion of $2 \, mol$ of an ideal gas from a volume of $10 \, dm^3$ to $100 \, dm^3$ at $27 \, ^oC$.

Match the following processes with their corresponding entropy changes:

$a$. Liquid to vapor conversion	$1$. $\Delta S = 0$
$b$. Reaction not spontaneous at any temperature,$\Delta H = (+)$	$2$. $\Delta S = (+)$
$c$. Reversible expansion of an ideal gas	$3$. $\Delta S = (-)$

The total amount of energy in the universe is fixed,but

The entropy change involved in the conversion of $1 \, \text{mole}$ of liquid water at $373 \, K$ to vapour at the same temperature will be $[\Delta H_{vap} = 2.257 \, kJ/g]$. (in $, kJ/K$)

If the enthalpy of fusion of a compound at $27 \, ^\circ C$ is $2930 \, J/mol$,what is the entropy change in $J/mol \cdot K$?