Calculate the solubility of Cu(OH)₂ in a solution buffered at pH = 8.50. (K_sp = 1.6 × 10^-19) A) 5.7 × 10^-10 M B) 1.6 × 10^-2 M C) 1.8 × 10^-7 M D) 1.6 × 10^-8 M E) none of these

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Quizplus · Accepted Answer

The solubility of Cu(OH)₂ can be calculated using the following equilibrium equation: Cu(OH)₂(s) ⇌ Cu2+(aq) + OH-(aq) + HS(-)(aq) The equilibrium constant expression for this reaction is: K = [Cu2+][OH-][HS-] Since the solution is buffered at pH = 8.50, we can assume that the concentration of OH- is equal to the concentration of H+ ions, which can be calculated from the pH: pH = -log[H+] 8.50 = -log[H+] [H+] = 3.16 × 10^-9 M Therefore, [OH-] = 3.16 × 10^-9 M Substituting this value into the equilibrium constant expression and using the given value of Ksp, we can solve for the solubility of Cu(OH)₂: Ksp = [Cu2+][OH-][HS-] 1.6 × 10^-19 = [Cu2+](3.16 × 10^-9)[HS-] [Cu2+] = (1.6 × 10^-19)/(3.16 × 10^-9) = 5.06 × 10^-11 M Therefore, the solubility of Cu(OH)₂ in a pH = 8.50 buffer solution is 5.06 × 10^-11 M, which corresponds to answer choice D.

Calculate the Solubility of Cu(OH)2 in a Solution Buffered at PH

Calculate the Solubility of Cu(OH)₂ in a Solution Buffered at PH