# Problem: A solution is prepared by mixing 100.0 mL of 1.0 X 10 -2 M Pb(NO3)2 and 100.0 mL of 1.0 X 10-3 M NaF. Will PbF2(s) (Ksp = 4 X 10 -8) precipitate?

###### FREE Expert Solution

We’re being asked to determine if a precipitate will form by mixing 100.0 mL of 1.0 X 10 -2 M Pb(NO3)2 and 100.0 mL of 1.0 X 10-3 M NaF.

For this, we need to compare the reaction quotient (Q) vs. the solubility product constant (Ksp)

Recall that when:

• Q > Ksp: the solution is supersaturated and a precipitate will form. Reactants are favored.

• Q = Ksp: the solution is at equilibrium and no precipitate will form.

• Q < Ksp: the solution is unsaturated and no precipitate will form. Products are favored.

The expected precipitate is PbF2

The dissociation of PbF2 in water is as follows:

PbF2(s)  Pb2+(aq) + 2 F(aq)

Step 1. Calculate the concentration of each

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###### Problem Details

A solution is prepared by mixing 100.0 mL of 1.0 X 10 -2 M Pb(NO3)2 and 100.0 mL of 1.0 X 10-3 M NaF. Will PbF2(s) (Ksp = 4 X 10 -8) precipitate?