Calculate the molar concentration of uncomplexed Zn²⁺ in a solution that contains 0.20 mol of Zn(NH₃)₄²⁺ per liter. The overall K_f for Zn(NH₃)₄²⁺ is 3.8 * 10⁹.

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First, we need to use the given equilibrium constant to calculate the molar concentration of complexed Zn(NH₃)₄²⁺ in the solution: K_f = [Zn(NH₃)₄²⁺]/[Zn²⁺][NH₃][₄] 3.8 F1F1F1S1F1F1F10 10⁹ = [0.20]/[Zn²⁺][NH₃][₄] [Zn²⁺] = 0.20/[NH₃][₄]*3.8 F1F1F1S1F1F1F10 10⁹ Then, we use stoichiometry to find the molar concentration of uncomplexed Zn²⁺: [Zn²⁺]total = [Zn²⁺] + [Zn(NH₃)₄²⁺] [Zn²⁺] = [Zn²⁺]total - [Zn(NH₃)₄²⁺] We don't know the value of [Zn(NH₃)₄²⁺], but we can assume that it is much smaller than [Zn²⁺]total since the equilibrium constant is also small. This means we can simplify the equation to: [Zn²⁺] = [Zn²⁺]total (because [Zn(NH₃)₄²⁺] is negligible compared to [Zn²⁺]total) Lastly, we substitute the value of [Zn²⁺] into the equation we found earlier: [Zn²⁺] = 0.20/[NH₃][₄]*3.8 F1F1F1S1F1F1F10 10⁹ [Zn²⁺] = 2.9 F1F1F1S1F1F1F10 10^-³ M

Calculate the Molar Concentration of Uncomplexed Zn2+ in a Solution

Calculate the Molar Concentration of Uncomplexed Zn²⁺ in a Solution