Use the following information to calculate the solubility product constant, K_sp, for CuCl. A saturated solution of CuCl in water was prepared and filtered. From the filtrate, 1.0 L was measured out into a beaker and evaporated to dryness. The solid CuCl residue recovered in the beaker was found to weigh 0.041g. A)K _sp = 1.7 × 10 ^y9 B)K _sp = 1.7 × 10 ^y7 C)K _sp = 1.7 × 10 ⁻⁵ D)K _sp = 4.3 × 10 ⁻⁴ E)K _sp = 2.1 × 10 ⁻²

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CuCl(s) ⇌ Cu+ + Cl- Let the equilibrium concentration of Cu+ and Cl- be x and y respectively. The solubility product constant, K_sp can be expressed as: K_sp = [Cu+][Cl-] At equilibrium, [Cu+] = [Cl-] = x (since 1 mole of CuCl dissociates into 1 mole of Cu+ and 1 mole of Cl-) K _sp = x^2 To find x, we need to use the mass of CuCl residue recovered. Mass of CuCl = 0.041g Molar mass of CuCl = 63.55 + 35.45 = 99.0 g/mol Number of moles of CuCl = mass/molar mass = 0.041/99.0 = 4.14 × 10^-4 mol Volume of filtrate used = 1.0 L Concentration of CuCl in the original saturated solution = number of moles/volume = 4.14 × 10^-4/1.0 = 4.14 × 10^-4 M At equilibrium, [Cu+] = [Cl-] = x Therefore, x = 4.14 × 10^-4 M K_sp = x^2 = (4.14 × 10^-4)^2 = 1.70 × 10^-7 Therefore, the best choice is B, which is 1.7 × 10^-7, in closest agreement with the calculated value.

Use the Following Information to Calculate the Solubility Product Constant