Question

using the table of standard formation enthalpies that youll find under the aleks data tab, calculate the reaction enthalpy of this reaction under standard conditions: fe₂o₃(s) + 3 co(g) → 2 fe(s) + 3 co₂(g) round your answer to the nearest kj.

Explanation:

Step1: Recall reaction enthalpy formula

$\Delta H^\circ_{\text{rxn}} = \sum \Delta H^\circ_f(\text{products}) - \sum \Delta H^\circ_f(\text{reactants})$

Step2: List standard formation enthalpies

From standard tables:
$\Delta H^\circ_f(\text{Fe}_2\text{O}_3(s)) = -824.2\ \text{kJ/mol}$, $\Delta H^\circ_f(\text{CO}(g)) = -110.5\ \text{kJ/mol}$,
$\Delta H^\circ_f(\text{Fe}(s)) = 0\ \text{kJ/mol}$ (element), $\Delta H^\circ_f(\text{CO}_2(g)) = -393.5\ \text{kJ/mol}$

Step3: Calculate product enthalpy sum

$2 \times 0 + 3 \times (-393.5) = -1180.5\ \text{kJ}$

Step4: Calculate reactant enthalpy sum

$1 \times (-824.2) + 3 \times (-110.5) = -824.2 - 331.5 = -1155.7\ \text{kJ}$

Step5: Compute reaction enthalpy

$\Delta H^\circ_{\text{rxn}} = -1180.5 - (-1155.7) = -24.8\ \text{kJ} \approx -25\ \text{kJ}$

Answer:

-25