Question

I need help figuring out the #9 for both trials. I also wanted to know if #8 is correct. Show work please!

B. Molar Solubility of Calcium Hydroxide in the Presence of a Common Ion
	Trial 1	Trial 2
1. Volume of saturated Ca(OH)2 with added CaCl2 solution (mL)	25	25
2. Concentration of standardized HCl solution (mol/L)	0.0465
3. Buret reading, initial (mL)	0	0
4. Buret reading, final (mL)	39.4	42.6
5. Volume of HCl added (mL)	39.4	42.6
6. Moles of HCl added (mol)	0.00183	0.00198
7. Moles of OH- in saturated solution (mol)	0.0366	0.0396
8. [OH-], equilibrium (mol/L)	0	0.0238
9. Molar solubility of Ca(OH)2 with added CaCl2 (mol/L)
10. Average molar solubility of Ca(OH)2 with added CaCl2 (mol/L)