Aluminum oxide can be reduced to aluminum metal using carbon, the other reaction product being carbon monoxide.Determine the enthalpy change when 12.5 g of aluminum is produced by this method.[$\Delta$H°_f(carbon monoxide)= -110.5 kJ/mol; $\Delta$H°_f(aluminum oxide)= -1669.8 kJ/mol]

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The enthalpy change for the reaction can be calculated using the following equation:$$\Delta H° = \sum \Delta H°_f \text{(products)} - \sum \Delta H°_f \text{(reactants)}$$where $\Delta H°_f$ is the standard enthalpy of formation.For the reaction:$$2Al_2O_3 + 3C \rightarrow 4Al + 3CO$$The enthalpy change is:$$\Delta H° = [4\Delta H°_f(Al) + 3\Delta H°_f(CO)] - [2\Delta H°_f(Al_2O_3) + 3\Delta H°_f(C)]$$Substituting the given values:$$\Delta H° = [4(0 kJ/mol) + 3(-110.5 kJ/mol)] - [2(-1669.8 kJ/mol) + 3(0 kJ/mol)]$$$$\Delta H° = -331.5 kJ/mol + 3339.6 kJ/mol = 3008.1 kJ/mol$$To determine the enthalpy change when 12.5 g of aluminum is produced, we need to convert the mass of aluminum to moles:$$12.5 g Al \times \frac{1 mol Al}{26.98 g Al} = 0.463 mol Al$$Therefore, the enthalpy change is:$$\Delta H° = 3008.1 kJ/mol \times 0.463 mol = 310 kJ$$Therefore, the correct answer is A) 310 kJ.

Aluminum Oxide Can Be Reduced to Aluminum Metal Using Carbon Δ\DeltaΔ

Aluminum Oxide Can Be Reduced to Aluminum Metal Using Carbon $\Delta$