Question

1. the equilibrium constant for the following reaction below at constant temperature is keq = 4.5. if so₂ = 1.5 mol/l, o₂ = 2.0 mol/l, and so₃ = 2.4 mol/l, find qeq and determine in which direction the reaction will proceed to establish equilibrium. (2 marks)

2 so₂(g) + o₂(g) ⇌ 2 so₃(g)

overall expectations:
e2 and e3

not yet | level 4⁺⁺ 100% | level 4⁺ 95% | level 4⁻ 85%
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demonstrates the concept chemical equilibrium with a high degree of effectiveness and accuracy: - understands all the required concepts - did all required math correctly - made correct conclusions based on the correct analysis - explanation is succinct and uses proper terminology

demonstrates the concept chemical equilibrium, with a high degree of effectiveness and accuracy: - misread some information from the question or - used incorrect form or - slight error in solution

demonstrates the concept chemical equilibrium, with a high degree of effectiveness and accuracy: - made a math error or - made a small conceptual error or used a formula incorrectly

Explanation:

Step1: Recall Qeq formula

For reaction \( \ce{2SO_{2(g)} + O_{2(g)}
ightleftharpoons 2SO_{3(g)}} \), \( Q_{eq}=\frac{[\ce{SO_3}]^2}{[\ce{SO_2}]^2[\ce{O_2}]} \).

Step2: Substitute values

Given \( [\ce{SO_2}]=1.5\ \text{mol/L} \), \( [\ce{O_2}]=2.0\ \text{mol/L} \), \( [\ce{SO_3}]=2.4\ \text{mol/L} \).
Substitute into formula:
\( Q_{eq}=\frac{(2.4)^2}{(1.5)^2\times2.0} \)
Calculate numerator: \( (2.4)^2 = 5.76 \)
Calculate denominator: \( (1.5)^2\times2.0 = 2.25\times2.0 = 4.5 \)
Thus, \( Q_{eq}=\frac{5.76}{4.5}=1.28 \).

Step3: Compare Qeq and Keq

Given \( K_{eq}=4.5 \). Since \( Q_{eq}=1.28 < K_{eq}=4.5 \), reaction proceeds forward (toward products) to reach equilibrium.

Answer:

\( Q_{eq}=1.28 \), reaction proceeds forward (toward \( \ce{SO_3} \) formation).