Question

Use the values of ∆H^o_f given below to calculate ∆H^o_rxn for the following reaction:

C₂H₅OH (l)+ 3O₂(g) → 2CO₂(g) + 3H₂O(g)

Given:	∆Hof (kJ/mol)
C2H5OH (l)	-278
O2(g)	0
CO2(g)	-394
H2O(g)	-242

Use kJ for your answer. ΔH^o_rxn =

Answer 1

we have:

Hof(C2H5OH) = -278.0 KJ/mol

Hof(O2) = 0.0 KJ/mol

Hof(CO2) = -394.0 KJ/mol

Hof(H2O) = -242.0 KJ/mol

we have the Balanced chemical equation as:

C2H5OH + 3 O2 ---> 2 CO2 + 3 H2O

deltaHo rxn = 2*Hof(CO2) + 3*Hof(H2O) - 1*Hof( C2H5OH) - 3*Hof(O2)

deltaHo rxn = 2*(-394.0) + 3*(-242.0) - 1*(-278.0) - 3*(0.0)

deltaHo rxn = -1236 KJ

Answer: -1236 KJ