In: Chemistry
1. Write the solubility equilibrium and the solubility product expression for the following sparingly soluble salts.
CaCO3
Cu2S
Sb2S3
2. The solubility of silver bromide, AgBr, at 25
a) CaCO3
Ca+2 + CO3-2
S S S
Ksp = [ Ca+2][CO3-2]
Ksp = S2
b) Cu2S
2Cu+ + S-2
S 2 S S
Ksp = [ Cu+]2[S-2]
Ksp = (2S)2(S) = 4S3
c) Sb2S3
2Sb+3 + 3S-2
S 2S 3S
Ksp = [Sb+3]2[S-2 ]3
= [2S]2[3S ]3
= 108S5
2) for AgBr
Ksp = S2
Ksp = (8.8.x.10-7)2
= 77.44 x 10-14