Question

Carbon reacts with oxygen to produce carbon dioxide (CO2 (g), Delta.Hf = –393.5 kJ/mol) according to the equation below.

Upper C (s) plus 2 upper O subscript 2 (g) right arrow upper C upper O subscript 2 (g).

What is the enthalpy change of the reaction?
Use Delta H r x n equals the sum of delta H f of all the products minus the sum of delta H f of all the reactants..
–393.5 kJ
–196.8 kJ
196.8 kJ
393.5 kJ

Answer 1

ΔHrxn = ΔHf(products) − ΔHf(reactants) = (−393.5 kJ) − (0 + 0) = −393.5 kJ.