Answer
See below
Work Step by Step
The reaction is exothermic, so $Δ_{r}$H° should be negative. Also, a gas and an aqueous solution are formed, so $Δ_{r}$S° should be positive. The calculated values are
$Δ_{r}$H° = −183.32 kJ/mol-rxn (with a negative sign as
expected) and $Δ_{r}$S° = −7.7 J/K ∙ mol-rxn
The entropy change is slightly negative, not positive
as predicted. The reason for this is the negative
entropy change upon dissolving NaOH. The $OH^{-}$ ions in water hydrogen-bond with water
molecules, an effect that also leads to a small, negative entropy change.
