Chapter 9.6, Problem 38PP

Classify each of the following as exothermic or endothermic, and give the $\Delta$ H for each:

$\begin{array}{l}a.C_{3}Hg\left(g\right)+5O_2\left(g\right)\stackrel{\Delta }{\to }3C{O}_2\left(g\right)+4H_{2}O\left(g\right)+2220kJ\hfill \\ b.2Na\left(s\right)+C{1}_2\left(g\right)\to 2NaCI\left(s\right)\text{ + }819\text{ kJ}\hfill \\ c.PC{I}_5\left(g\right)+67\text{ kJ}\to PC{I}_3\left(g\right)+C{1}_2\left(g\right)\hfill \end{array}$