When hydrazine (N2H4) reacts with nitrogen gas, hydrogen peroxide and the water are formed. Write down a balanced reaction and calculate delta H for the reaction from the following thermo chemical data.
H2 + O2 ==>H2O delta H= -187.8KJ
N2H4 + O2 ==> N2 +2H2O delta H=-621.6 KJ
H2 + 0.5O2 ==>H2O delta H= -285.8KJ