What is the unit of entropy?

$A$ 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 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?

In which of the following processes does the entropy decrease?

Identify from the following physical transformations that exhibits a decrease in entropy.

Observe the following reactions:
$I$. $CaCO_{3(s)} \rightarrow CaO_{(s)} + CO_{2(g)}$
$II$. $Cl_{2(g)} \rightarrow 2 Cl_{(g)}$
$III$. $H_2O_{(l)} \rightarrow H_2O_{(s)}$
Identify the reactions in which entropy increases.