# A student decides to react HCl with NaOH in 50 g of H2O. The reaction produces heat.. What is the balanced chemical equation for the reaction?

$H C l \left(a q\right) + N a O H \left(a q\right) \rightarrow N a C l \left(a q\right) + {H}_{2} O \left(l\right) + {\Delta}_{\text{rxn}}$
Now not only does the given reaction observes stoichiometry with respect to atoms and molecules, it also observes stoichiometry with respect to the heat of reaction. $\Delta H$ is usually reported per mole of reaction as written, and can usually be precisely measured.