3O2(g) + C4H8N2O3(s) CH4NO2(s) + 3CO2(g)+ 2H2O(l) Given the standard enthalpy of formation of these substances are a, b, c, d, e kJ/mol, respectively (You should know how to look into these numbers). Q: But this is all at 25 C (where experiments are easily carried out, and data tabulated). What about biological temperatures? Example: What happens when you drink some water?