Chemistry

Problem

Aluminum hydroxide,

\mathrm{Al(OH)_3}

, has

K_{sp}=3.0\times10^{-34}

. What hydroxide ion concentration, in M, is required to begin precipitating

\mathrm{Al(OH)_3}

from a

2.0\times10^{-4}\;\text{M}

\mathrm{Al^{3+}}

solution at

25^\circ\text{C}

? a)

1.1\times10^{-9}\;\text{M}

2.7\times10^{-12}\;\text{M}

1.1\times10^{-10}\;\text{M}

1.2\times10^{-15}\;\text{M}