Based on the above reaction what energy change occurs when 1.2 moles of methane (ch4) reacts

1 mole of CH4 releases - 434kJ of energy (the coefficient on CH4 would be 1, and therefore there is 1 mole of CH4 in that equation). Since we want to find out how much energy 1.2 moles would release, we have to use that information as a conversion factor. Start with 1.2 moles, multiply by. 434kJ/1 mole. When 1.2 moles of methane react the released energy is: 434 x 1.2 = 520 kJ = 5.2 x 10^5 J