Answer:
equilibrium constant Kc = 8.52 × 10⁻⁴
Explanation:
You need The equations for the dissolution of AgI(s) and the stability constant of the complex [Ag(CN)₂]⁻(aq)
The equations for the dissolution of AgI(s) is:
AgI(s) ⇔ Ag⁺(aq) + I⁻(aq) Ksp = [Ag⁺(aq) I⁻(aq)]
The stability constant of the complex [Ag(CN)₂]⁻(aq) is:
Ag⁺(aq) + 2CN⁻(aq) ⇔ [Ag(CN)₂]⁻(aq) Kfb2 = [tex]\frac{[Ag(CN)_{2}(aq)]^{-} }{[Ag^{+}(aq)][2CN^{-}(aq)] }[/tex]
Adding the equations for the dissolution of AgI(s) and the stability constant of the complex [Ag(CN)₂]⁻(aq) we get the required reaction. so the equilibrium constant for the reaction is the product of the individual equilibrium constants:
AgI(s) + 2CN⁻(aq) ⇔ [Ag(CN)₂]⁻(aq) + I⁻(aq)
Kc = Ksp × Kfb2 = [Ag⁺(aq) I⁻(aq)] × [tex]\frac{[Ag(CN)_{2}(aq)]^{-} }{[Ag^{+}(aq)][2CN^{-}(aq)] }[/tex] = [tex]\frac{[Ag(CN)_{2}(aq)]^{-} [I(aq)^{-}] }{[2CN^{-}(aq)] }[/tex]
Kc = 8.52 × 10⁻¹⁷ × 1 × 10²¹ = 8.52 × 10⁻⁴