Question

Estimate the solubility of m(oh)2 in a solution buffered at ph = 7.0, 10.0, and 14.0.

Answer 1

The solubility of a compound depends on the pH of the solution. In general, metal hydroxides like M(OH)2 are more soluble in basic or alkaline solutions.

Step-by-step explanation:

The solubility of a compound depends on the pH of the solution. In general, metal hydroxides like M(OH)2 are more soluble in basic or alkaline solutions. The solubility decreases as the pH becomes more acidic. So, in a buffered solution at pH 7.0, the solubility of M(OH)2 would be lower compared to a solution buffered at pH 10.0 or 14.0.

For example, if we consider the solubility of Ca(OH)2 (calcium hydroxide), it would be lowest in a solution buffered at pH 7.0, slightly higher in a solution buffered at pH 10.0, and highest in a solution buffered at pH 14.0.

Answer 2

When M(OH)2 dissolves we have M(OH)2 which produces M2+ and 2OHâ’ pH + pOH=14 At ph =7; we have 7+pOH=14 pOH=14â’7 = 7 Then [OHâ’]=10^(â’pOH) [OH-] = 10^(-7) = 1* 10^(-7) At ph = 10. We have, pOH = 4. And [OH-] = 10^(-4) = 1 * 10^(-4) Finally ph = 14. We have, pOH = 0 And then [OH-] = 10^(-0) -----anything raised to zero power is 1, but (-0)... So [OH-] = 1