A lab technician adds 0.020 mol of KCl to 1.00 L of 0.0050 M Pb(NO 3 ) 2 . K sp

ID: 967188 • Letter: A

Question

A lab technician adds 0.020 mol of KCl to 1.00 L of 0.0050 M Pb(NO3)2. Ksp = 1.7 × 10–5 for PbCl2. Which of the following statements is correct?

Lead chloride precipitates until the solution is saturated.

The solution is unsaturated and no precipitate forms.

The concentration of lead ions is reduced by the addition of the chloride ions.

One must know Ksp for lead nitrate to make meaningful predictions on this system.

The presence of KCl will raise the solubility of Pb(NO3)2.

Lead chloride precipitates until the solution is saturated.

The solution is unsaturated and no precipitate forms.

The concentration of lead ions is reduced by the addition of the chloride ions.

One must know Ksp for lead nitrate to make meaningful predictions on this system.

The presence of KCl will raise the solubility of Pb(NO3)2.

Q = [Pb+2][Cl-]^2

Q = (0.005)(0.02)^2 = 0.000002 = 2*10^-6

Since

Q << Ksp,

there is no precipitation

The solution is unsaturated and no precipitate forms.

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.