Example: $50\mathrm{.}0mL$ dilute $AgN{O}_3$ is added to a solution with $O{H}^{-}$ions in a coffee cup calorimeter. $A{g}_{2}O$ precipitates and the temperature of the liquid goes from $23\mathrm{.}78C$ to $25\mathrm{.}19C.$ Assume that the mixture has the same specific heat as water. Calculate $"q_{\text{s}\text{u}\text{r}}"$ for a mass of $150g.$ Is the reaction exothermic or endothermic?