Chemical energy is released or absorbed from reactions in various forms. The most easily measurable form of energy comes in the form of heat, or enthalpy. The enthalpy of a reaction can be calculated from the heats of formation of the substances involved in the reaction: n = (products) - . (reactants) where n represents the stoichiometric coefficients. Part A Calculate the standard enthalpy change for the reaction Use the following data: Substance (kJ/mol) A B C D Express your answer to three significant figures and include the appropriate units. View Available Hint(s) AH 309 kJ Submit -263 -383 183 -483 Correct Part B Previous Answers 2A+B=2C+2D For the reaction given in Part A, how much heat is absorbed when 3.60 mol of A reacts? Express your answer to three significant figures and include the appropriate units. View Available Hint(s)