Entropy is maximum in case of

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

In which of the following processes does entropy decrease?

For the vaporization of water at $1 \, \text{atm}$ pressure,the liquid water and water vapor are in equilibrium. What is the temperature in $K$?
$H_2O_{(l)} \rightleftharpoons H_2O_{(g)}$ [at $1 \, \text{atm}$ pressure] [$\Delta S = 120 \, J K^{-1}$ and $\Delta H = +45.0 \, kJ$]

The molar heat of vaporisation of a liquid is $6 \ kJ \ mol^{-1}$. If the entropy change is $16 \ J \ mol^{-1} \ K^{-1}$,the boiling point of the liquid is:

The enthalpy change for the conversion of water into vapor at $27^\circ C$ is $30 \ kJ/mol$. The entropy change for this process in $J/mol \ K$ is: