The K_sp of Al(OH)₃ is 2 $\times$10^-³².At what pH will a 0.5 M Al³⁺ solution begin to show precipitation of Al(OH)₃?

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Quizplus · Accepted Answer

The Ksp expression for Al(OH)3 is:Ksp = [Al3+][OH-]3At the point of precipitation, the ion product [Al3+][OH-]3 will be equal to Ksp.Substituting the given values into the Ksp expression, we get:2 x 10^-32 = [0.5 M][OH-]3Solving for [OH-], we get:[OH-] = 2 x 10^-11 MTo find the pH at which precipitation will begin, we use the pOH equation:pOH = -log[OH-]pOH = -log(2 x 10^-11) = 10.7pH = 14 - pOH = 14 - 10.7 = 3.3Therefore, the 0.5 M Al3+ solution will begin to show precipitation of Al(OH)3 at a pH of 3.3, which is closest to choice A) 3.5.

The Ksp of Al(OH)3 Is 2 ×\times× 10-32

The K_sp of Al(OH)₃ Is 2 $\times$ 10^-³²