Answer:
[tex]\large \boxed{\text{-1276 kJ/mol}}[/tex]
Explanation:
You calculate the energy required to break all the bonds in the reactants.
Then you subtract the energy needed to break all the bonds in the products.
CH₃CH₂OH + 3O₂ ⟶ 2CO₂ + 3H₂O
Bonds: 5C-H 1C-C 1C-O 1O-H 3O=O 4C=O 6O-H
D/kJ·mol⁻¹: 413 347 358 467 495 799 467
[tex]\Delta H = \sum{D_{\text{reactants}}} - \sum{D_{\text{products}}}\\\sum{D_{\text{reactants}}} = 5 \times 413 + 1 \times 347 + 1 \times 358 + 1 \times 467 + 3 \times 495 = 3237 + 1485\\=\text{4722 kJ}\\\sum{D_{\text{products}}} = 4 \times 799 + 6 \times 467 =3196 + 2802 = \text{5998 kJ}\\\Delta H = 4722 - 5998= \textbf{-1276 kJ} \\ \text{The overall energy change is $\large \boxed{\textbf{-1276 kJ/mol}}$}.[/tex]
