For A + B ⇌ 2C, the equilibrium concentrations are [A] = 1 mol/dm³, [B] = 4 mol/dm³ and [C] = 4 mol/dm³. What is Kc?
Answer and explanation
Correct answer: B. 4
- Step 1: Kc = [C]² / ([A][B]). Step 2. Kc = 4² / (1 × 4) = 4. Answer: 4. Why not the others: 1 is what you get if you forget to square [C]. 0.25 is what you get if you invert the expression. 2 is what you get if you multiply [C] by the coefficient instead of squaring.
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