Chemical formula and heat
The best way to solve this problem is to look at the $\Delta H$ charts found online. Using the simple equation below will give you the answer.


  $$\sum \Delta H_{\text{Products}} - \sum \Delta H_\text{Reactants} = \Delta H_{\text{Reaction}}$$
  If the $\Delta H$ is positive in sign then the reaction is endothermic and if it is negative in sign then it is exothermic.