Calculate the heat of reaction for the equation: HgO (s) --> Hg (l) + O2 (g)?

Report your answer in kJ with 3 Sig Figs.

Compound: Heat of Formation
(kJ/mol)
HgO (s) -90.83
Hg (l) 0
O2 (g) 0

The heat of the reaction for the previous equation means the reaction is ____ (Endo/Exo), because it ____ energy from its surroundings.