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Calculation of calcium hydroxide solubility
The data we need is:
Volume of calcium hydroxide solution titrated = 10.0 cm3
Concentration of hydrochloric acid = 0.05M
Start reading on burette = 3.0 cm3
Final reading on burette = 9.1 cm3
Titre = 9.1 - 3.0 = 6.1 cm3
Normally we would have at least two results and these would need averaging after ignoring any values which were clearly inconsistent (so call outliers)
Number of moles of hydrochloric acid = 0.05 × 6.1/1000
|
Ca(OH)2(aq) + 2HCl(aq) ⇒ CaCl2(aq) + 2H2O(l) |
\ number of moles of calcium hydroxide in 10.0 cm3 = ½ × 0.05 × 6.1/1000
\ concentration of calcium hydroxide = (½ × 0.05 × 6.1/1000)/0.010 = 0.015 mol dm-3
Ca(OH)2 = 74
\ concentration of calcium hydroxide = 0.015 × 74 = 1.1 g dm-3
You can check the accepted value for the solubility of calcium hydroxide in the data book. This is given in mol/100g of water. It should be relatively straightforward to change this value into mol/1000g of water, although technically this is not the same as concentration.