a) The molar solubility of calcium fluoride, CaF2, is 2.1 × 10-4 mol L-1. From this we can calculate the Ksp of CaF2 to be

a) 9.3 × 10-12.
b) 1.9 × 10-11.
c) 3.7 × 10-11.
d) 8.8 × 10-8.

b)What is the molar solubility of calcium fluoride, CaF2 (Ksp = 3.9 × 10-11 ), in a 0.10M sodium fluoride, NaF, solution?

a) 3.9 × 10-9
b) 1.0 × 10-9
c) 1.0 × 10 -5
d) 2.2 × 10-4