Which state functions are required to understand the second law of thermodynamics?

Which of the following reactions has a positive entropy change?

What will be $\Delta S$ for the reaction: $2A + 3B \to 4C + 5D$ (in $J \ K^{-1}$)?
Given:
$\Delta S_A^o = 100 \ J \ mol^{-1} \ K^{-1}$
$\Delta S_B^o = 120 \ J \ mol^{-1} \ K^{-1}$
$\Delta S_C^o = 200 \ J \ mol^{-1} \ K^{-1}$
$\Delta S_D^o = 150 \ J \ mol^{-1} \ K^{-1}$

The enthalpy of vapourization of a liquid is $30 \ kJ \ mol^{-1}$ and entropy of vapourization is $75 \ J \ mol^{-1} \ K^{-1}$. The boiling point of the liquid at $1 \ atm$ is.......$K$

Explain entropy and spontaneity of reactions.

One mole of an ideal gas expands adiabatically and reversibly from its initial pressure to half of its initial pressure. What will be the value of $\Delta S$ in $J \ K^{-1} \ mol^{-1}$? $[\ln 2 = 0.693$ and $R = 8.314 \ J \ mol^{-1} \ K^{-1}]$