Enthalpy of decomposition is measured in kilojoules per mole, so we need to know how much material we’re working with.
Ten grams of hydrogen peroxide is 0.294 moles (formula weight: 34.014 grams per mole), so we can run the reaction 0.147 times (0.294 moles divided by the two moles per run requirement). This means the reaction has a heat loss equivalent to:
0.147 x -190 kJ
or -27.93 kJ through the reaction.
