How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF₂ at 25^$\circ$C to reduce the [Pb²⁺] to 1.0 * 10^-6 M The K_sp for PbF₂ at 25 ^$\circ$C is 4.0 * 10^-8.

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The correct answer is A because the addition of NaF to a saturated solution of PbF2 will cause the [Pb2+] to decrease due to the common ion effect. The Ksp expression for PbF2 is:Ksp = [Pb2+][F-]2If we add NaF to the solution, the [F-] will increase, which will cause the [Pb2+] to decrease in order to maintain the Ksp value. The amount of NaF that needs to be added to reduce the [Pb2+] to 1.0 * 10-6 M can be calculated using the Ksp expression:Ksp = [Pb2+][F-]24.0 * 10-8 = (1.0 * 10-6)[F-]2[F-] = 2.0 * 10-3 MThe moles of NaF that need to be added to the solution can be calculated using the following equation:moles of NaF = [F-] * volume of solutionmoles of NaF = (2.0 * 10-3 M) * (1.00 L)moles of NaF = 0.20 mol

How Many Moles of NaF Must Be Dissolved in 1 ∘\circ∘

How Many Moles of NaF Must Be Dissolved in 1 $\circ$