predict the sign of DSsys for each of the following processes:?

Question

Without referring to tabulated thermodynamic information, predict the sign of DSsysfor each of the following processes. (For each statement select P-Positive, or N-Negative. Then enter all 6 correct letters, in order: PPNNPN, for example.)

1. NH3(g) + HBr(g) -> NH4Br(s)
2. NaClO3(s) -> Na+(aq) + ClO3-(aq)
3. D) 2NO2(g) -> N2O4(g)
4. E) CaCO3(s) + 2HCl(aq) -> CaCl2(aq) + H2O(l) + CO2(g)
5. F) 2KClO3(s) -> 2KCl(s) + 3O2(g)

Thanks for the help! :)

Answer 1

The trick is to realize that the entropy of gases is bigger than solids or liquids because of the large contribution from the translational degrees of freedom (and more importantly the large number of accessible translational energy levels).

So apart from the (aq) ones it is problem solved.
For the (aq) reaction I would not want to guess as sometimes the extra order from the formation of a "solvent shell" around the ion off-sets any gain from breaking up the solid.