If 50.0 mL of 1.2 × 10⁻³ M Pb(NO₃)₂ are added to 50.0 mL of 2.0 × 10⁻⁴ M Na₂S, what takes place?
Ksp(PbS) = 7 × 10⁻²⁹
a) a precipitate of NaNO₃ forms.
b) no precipitate forms.
c) a precipitate of PbS forms.
d) a precipitate of Na₂S forms.
e) a precipitate of Pb(NO₃)₂ forms.