Question

write the concentration equilibrium constant expression for this reaction. cr₂o₇²⁻(aq)+6i⁻(aq)+14h⁺(aq)→3i₂(s)+2cr³⁺(aq)+7h₂o(l)

Explanation:

Step1: Recall the formula for equilibrium constant expression

The general formula for a reaction \(aA + bB
ightleftharpoons cC + dD\) is \(K_c=\frac{[C]^c[D]^d}{[A]^a[B]^b}\), where \(A,B\) are reactants and \(C,D\) are products. Solids (\(s\)) and liquids (\(l\)) are excluded from the expression.

Step2: Identify reactants and products in the given reaction

Reactants: \(\text{Cr}_2\text{O}_7^{2 -}(aq)\), \(\text{I}^-(aq)\), \(\text{H}^+(aq)\)
Products: \(\text{I}_2(s)\) (excluded as it is solid), \(\text{Cr}^{3+}(aq)\), \(\text{H}_2\text{O}(l)\) (excluded as it is liquid)

Step3: Write the equilibrium constant expression

Using the formula \(K_c=\frac{[\text{Cr}^{3+}]^2}{[\text{Cr}_2\text{O}_7^{2 -}][\text{I}^-]^6[\text{H}^+]^{14}}\)

Answer:

\(K_c=\frac{[\text{Cr}^{3+}]^2}{[\text{Cr}_2\text{O}_7^{2 -}][\text{I}^-]^6[\text{H}^+]^{14}}\)