Chapter 2, Problem 2.80E

Using Hess’s law, write out all of the formation reactions that add up to, and calculate ${\Delta }_{rxn}H(25°C)$ for, the following reaction: $2NaHC{O}_3\left(s\right)\to N{a}_{2}C{O}_3\left(s\right)+C{O}_2\left(g\right)+H_{2}O\left(l\right)$

(This reaction occurs when one uses baking soda to smother a fire in the kitchen.)