Question

Calculate the solubility of copper(II) hydroxide, Cu(OH)2, in g/L​

Answer 1

Ksp = [ Cu+² ] [ OH-] ²

molar mass Cu(oH )2 ==> M= 63.546 (1) + 16 (2) + 1 (2) = 97.546 g/mol

Ksp = [ Cu+² ] [ OH-] ²

Ksp [ cu (OH)2 ] = 2.2 × 10-²⁰

|__________|___Cu+² __|_2OH-____|

|Initial concentration(M)|___0__|_0______|

|Change in concentration(M)|_+S |__+2S__|

|Equilibrium concentration(M)|_S _|2S___|

Ksp = [ Cu+² ] [ OH-] ²

2.2 ×10-²⁰ = (S)(2S)²= 4S³

`s = \sqrt[3]{ \frac{2.2 * {10}^( - 20) }{4} } = 1.8 * {10}^( - 7)`

S = 1.8 × 10-⁷ M

The molar solubility of Cu(OH)2 is 1.8 × 10-⁷ M

Solubility of Cu (OH)2 =

`Cu (OH)2 = \frac{1.8 * {10}^( - 7) mol \:Cu (OH)2 }{1L} * (97.546 \: g \: Cu (OH)2)/(1 \: mol \: Cu (OH)2) \\ = 1.75428 * 10 ^( - 5)`

Solubility of Cu (OH)2 = 1.75428 × 10 -⁵ g/ L

I hope I helped you^_^