Respuesta :
Answer:
For 1: The solubility of magnesium hydroxide at 25°C is [tex]1.65\times 10^{-4}M[/tex]
For 2: The concentration of hydroxide ion in the saturated solution at 25°C is [tex]3.3\times 10^{-4}M[/tex]
Explanation:
- For 1:
The equation for the ionization of the magnesium hydroxide is given as:
[tex]Mg(OH)_2\leftrightharpoons Mg^{2+}+2OH^-[/tex]
s 2s
Expression for the solubility product of [tex]Mg(OH)_2[/tex] will be:
[tex]K_{sp}=[Mg^{2+}][OH^-]^2\\\\K_{sp}=s\times (2s)^2=4s^3[/tex]
We are given:
[tex]K_{sp}=1.8\times 10^{-11}[/tex]
Putting values in above equation, we get:
[tex]1.8\times 10^{-11}=4s^3\\\\s=1.65\times 10^{-4}M[/tex]
Hence, the solubility of magnesium hydroxide at 25°C is [tex]1.65\times 10^{-4}M[/tex]
- For 2:
Concentration of hydroxide ion in the solution = 2s = [tex](2\times 1.65\times 10^{-4})=3.3\times 10^{-4}M[/tex]
Hence, the concentration of hydroxide ion in the saturated solution at 25°C is [tex]3.3\times 10^{-4}M[/tex]
