Question

Explain with reason, sign convention of $\Delta S$ in the following conversion.

$C{O}_{2\left(g\right)}\to C{O}_{2\left(s\right)}$

Answer 1

$C{O}_{2\left(g\right)}\to C{O}_{2\left(s\right)}$

In the above process, the high disorder in gaseous state changes to less disorder in the solid state.

Hence, entropy decreases, $\Delta S<0$.

So, sign of $\Delta S$ is $-ve$.