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(I already have part A but still still include it anyways so youcan use its data to solve for parts B and C.

Chemical energy is released or absorbed from reactions invarious forms. The most easily measurable form of energy comes inthe form of heat, or enthalpy. The enthalpy of a reaction can becalculated from the heats of formation of the substances involvedin the reaction:

ΔH∘rxn=ΔH∘f(products)−ΔH∘f(reactants)

Entropy change, ΔS∘, is a measure of the number of energeticallyequivalent microstates introduced into the system during thereaction. The degree of spontaneity of a reaction is represented bythe Gibbs free energy, ΔG∘. The Gibbs free energy depends on boththe enthalpy and entropy changes that take place during thereaction:

ΔG∘=ΔH∘−TΔS∘

where T is standard temperature, 298 K.

Part A

Part complete

Calculate the standard enthalpy change for the reaction

2A+B⇌2C+2D

where the heats of formation are given in the followingtable:

Substance	ΔH∘f (kJ/mol)
A	-261
B	-425
C	175
D	-491

Express your answer in kilojoules.

ΔH∘rxn = 315 kJ  

Part B

For the reaction given in Part A, how much heat is absorbed when3.30 mol of A reacts?

Express your answer numerically in kilojoules.

Part C

For the reaction given in Part A, ΔS∘rxn is 41.0 J/K . What isthe standard Gibbs free energy of the reaction, ΔG∘rxn?

Express your answer numerically in kilojoules.