Identify the correct statements from the following. I. At $0 \mathrm{~K}$, the entropy of pure crystalline…
Identify the correct statements from the following.
I. At $0 \mathrm{~K}$, the entropy of pure crystalline materials approach zero.
II. Entropy for the process, $\mathrm{H}_2 \mathrm{O}(\mathrm{l}) \longrightarrow \mathrm{H}_2 \mathrm{O}(\mathrm{g})$ decreases.
III. Gibb's energy is a state function.
I, II, III
I, III
II, III
I, II
Solution
At $0 \mathrm{~K}$, the entropy of pure crystalline materials is zero.
$\therefore$ The statement (I) is correct as entropy approach zero, at absolute zero.
Statement (II) entropy for the process,
$\mathrm{H}_2 \mathrm{O}(l) \longrightarrow \mathrm{H}_2 \mathrm{O}(\mathrm{g})$ decreases is incorrect as entropy increases. The degree of randomness when water vaporises to gaseous state increases.
(III) Gibbs' energy is a state function is correct as the Gibbs' free energy depends on initial and final state only.
Hence, statement (I) and (III) are correct.