Question

is lead chloride more soluble in a .55M solution of CaCl2 or a .65M solhtion of HCL?

Answer 1

in CaCl2 solution :

CaCl2 concentration = 0.55 M

Cl concentration = 2 x 0.55 = 1.1 M

PbCl2 -------------------> Pb⁺² + 2 Cl^-

                                        S        2S                  in water

                                         S        2S + 1.1         (from CaCl2)

                                         S         1.1

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

1.2 x 10^-5 = S x 1.1^2

S = 9.92x 10^-6 M ----------------------------------(1)

in HCl solution:

HCl concentration = 0.65 M

Cl concentration = 0.65 M

PbCl2 -------------------> Pb⁺² + 2 Cl^-

                                        S          2S                  in water

                                         S        2S + 0.65        (from CaCl2)

                                         S         0.65

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

1.2 x 10^-5 = S x 0.65^2

S = 2.84 x 10^-5 M -----------------------------(2)

lead chloride solubility is more in HCl