Question

Calculate the standard enthalpy change for the reaction2A+B⇌2C+2D Use the following data: Substance ΔH∘f (kJ/mol) A -227 B -413 C 175 D -521 Express your answer to three significant figures and include the appropriate units (note: the problem asks for the standard enthalpy of the reaction as written, so the units are not 'per mol'). View Available Hint(s)

Answer 1

ΔH∘f = 175Kj

Step-by-step explanation:

Heat of Formation (ΔH∘f) is the amount of energy required or the amount of heat liberated or absorbed when 1mol of substance is formed as represented i a balanced chemical equation.

ΔH∘f = (2ΔHc + 2ΔHD) - (2ΔHA + ΔHB)

ΔH∘f = (2x175 + 2x(-521)) - (2x(-227) +(-413))

ΔH∘f = 350 - 1042 - (-454 -413)

ΔH∘f = -692 + 867

ΔH∘f = 175Kj