Solutions:
(a) 1 mol NaCl(aq). The two samples have the same number of ions,
but in the solid they are highly ordered, and in the solution they are
randomly dispersed.
(b) 1 mol SCl6. For similar compounds, entropy increases with molar
mass.
(c) 1 mol CO2 (g) . For equal numbers of moles of substances with the
same types of atoms in the same physical state, the more atoms per
molecule, the more types of motion available to it and, thus, the higher
its entropy.
(d) 4 mol S2. The two samples contain the same number of sulfur atoms,
but different numbers of molecules. Despite the greater complexity of
S8 , the greater number of molecules dominates in this case because
there are many more ways to arrange 4 moles of particles than one mole.
(e) 1 mol H2O(g). For a given substance entropy increases in the
sequence: solid < liquid < gas.
(f) Soup at 95oC. Entropy increases with increasing temperature.
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