Question

The solubility of Al(OH)₃ is measured and found to be 2.22×10^-7 g/L. Use this information to calculate a K_sp value for aluminum hydroxide.

K_sp =

Answer 1

gram molar mass of Al(OH)3 = 78g/mole

solubility of Al(OH)3                 = 2.22*10^-7g/L /78g/mole

                                                  = 2.22*10^-7/78   = 2.84*10^-9 mole/L

Al(OH)3 -------------> Al^+3 + 3OH^-

                                  s            3s

Ksp       = [Al^3+][OH^-]^3

              = s*(3s)^3

               = 27S^3

               = 27(2.84*10^-9)^3

               = 6.184*10^-25 >>>>>>>>>>>answer