We’re asked to determine if an increase in temperature will produce an increase or decrease in the mole fraction of acetic acid at equilibrium.
We’re given the carbonylation reaction to form acetic acid at temperatures above 25°C:
CH3OH (l) + CO (g) → CH3COOH (l)
Recall that the mole fraction is the ratio of the moles of acetic acid (solute) and the total moles of the solution.
To determine how the temperature affects the mole fraction of acetic acid for the given reaction, we need to do these steps:
Step 1. Determine whether the reaction is exothermic or endothermic by solving for ΔH°rxn at 25°C using standard values for H°f
- When ΔH > 0 (positive) → endothermic
- When ΔH < 0 (negative) → exothermic