The unit of entropy is

Which of the following statements is correct?

Change in entropy is positive for

When naphthalene is heated strongly,it undergoes sublimation. What happens to the entropy of the system?

$A$ system of $100 \ kg$ mass undergoes a process in which its specific entropy increases from $0.3 \ kJ \ kg^{-1} \ K^{-1}$ to $0.4 \ kJ \ kg^{-1} \ K^{-1}$. At the same time,the entropy of the surrounding decreases from $80 \ kJ \ K^{-1}$ to $75 \ kJ \ K^{-1}$. Find the $(\Delta S)_{universe}$ in $kJ \ K^{-1}$.

For which of the following processes is $\Delta S$ negative?