Excess Ca(OH)â‚‚ is shaken with water to produce a saturated solution. The solution is filtered, and a 50.00 mL sample titrated with HCl requires 11.21 mL of 0.0983 M HCl to reach the end point.
Calculate [tex]K_{sp}[/tex] for Ca(OH)₂. Compare your result with that in Appendix D. Do you think the solution was kept at 25°C?

Respuesta :

Answer:

The solubility product of calcium hydroxide is [tex]5.35\times 10^{-6}[/tex].

Explanation:

To calculate the concentration of acid, we use the equation given y neutralization reaction:

[tex]n_1M_1V_1=n_2M_2V_2[/tex]

where,

[tex]n_1,M_1\text{ and }V_1[/tex] are the n-factor, molarity and volume of acid which is [tex]HCl[/tex]

[tex]n_2,M_2\text{ and }V_2[/tex] are the n-factor, molarity and volume of base which is [tex]Ca(OH)_2[/tex].

We are given:

[tex]n_1=1\\M_1=?0.0983 M\\V_1=11.21 mL\\n_2=2\\M_2=?\\V_2=50.00 mL[/tex]

Putting values in above equation, we get:

[tex]1\times 0.0983 M\times 11.21 mL=2\times M_2\times 50.00 mL\\\\M_2=0.01102 M[/tex]

Molarity of calcium hydroxide solution = 0.01102 M

[tex]Ca(OH)_2\rightleftharpoons Ca^{2+}(aq)+2OH^-(aq)[/tex]

1 mole of calcium hydroxide gives 1 mole of  calcium ions and 2 moles of hydroxide ions.

[tex][Ca^{2+}]=1\times 0.01102 M=0.01102 M[/tex]

[tex][OH^{-}]=2\times 0.01102 M=0.02204 M[/tex]

Solubility product is given by:

[tex]K_{sp}=[Ca^{2+}][OH^-]^2[/tex]

[tex]=0.01102 M\times (0.02204 M)^2=5.35\times 10^{-6}[/tex]

The solubility product of calcium hydroxide is [tex]5.35\times 10^{-6}[/tex].