Heat of Reaction per Mole at Temperature T2 is change in enthalpy at T2. And is denoted by ΔHr2. Heat of Reaction per Mole at Temperature T2 is usually measured using the Joule Per Mole for Energy Per Mole. Note that the value of Heat of Reaction per Mole at Temperature T2 is always negative. Typically, the value of Heat of Reaction per Mole at Temperature T2 is greater than 0.