Question

Hydrogen peroxide decomposes according to the following:
H2O2--> H2O(l) + 1/2O2(g); deltaH = -98.2kJ
Calculate the change in enthalpy, deltaH, when 1.00g of Hydrogen peroxide decomposes

Answer 1

98.2 kJ is released for 1 mole H2O2 (and 1 mole is 34 g approximately. You can do it exactly.) Now, how much of a mole is 1 g H2O2? So 98.2 kJ x (1 g/34 g) = ?? kJ energy released for 1 g Hydrogen.