25.0 mL of calcium hydroxide solution was titrated with standard 0.0100 mol/dm³ hydrochloric acid solution. Add 3 drops of screened methyl orange indicator. The average titre value is 12.00 cm³.
25.0 mL of the calcium hydroxide dissolved in sodium hydroxide solution was titrated with standard 0.0100 mol/dm³ hydrochloric acid solution, and the average value is 20.00 cm³.
Calculate:
- The concentration of the hydroxide ions.
- The concentration of calcium ions.
- The solubility of the calcium hydroxide.
- The Ks of calcium hydroxide.