The PH at which Al(OH)3 dissolves to give a concentration of 10-3M of Al+3 ion is

To find the pH at which Al(OH)3 dissolves to give a concentration of 10^-3 M of Al+3 ion, we need to use the solubility product constant (Ksp) and the formula for pH.

1. Write the balanced chemical equation for the dissolution of Al(OH)3:

   Al(OH)3 (s) ⇌ Al+3 (aq) + 3OH- (aq)

2. Write the expression for the solubility product constant (Ksp):

   Ksp = [Al+3][OH-]^3

3. The Ksp of Al(OH)3 is 3 x 10^-34. If the concentration of Al+3 is 10^-3 M, we can substitute this into the Ksp expression and solve for [OH-]:

   3 x 10^-34 = (10^-3)[OH-]^3 [OH-] = (3 x 10^-31)^(1/3) = 3.14 x 10^-11 M

4. The pH is related to the pOH by the equation pH = 14 - pOH. To find the pOH, we use the formula pOH = -log[OH-]:

   pOH = -log(3.14 x 10^-11) = 10.5

5. Finally, substitute the pOH into the pH equation to find the pH:

   pH = 14 - 10.5 = 3.5

So, the pH at which Al(OH)3 dissolves to give a concentration of 10^-3 M of Al+3 ion is 3.5.