Question

Trail Information

	Trail 1	Trail 2	Trail 3
Amount of HCl used	18.50ml	19.41ml	19.70ml
Ca(OH)2 amount used	33.9ml	25.65	15.95

1. Calculate the moles of H+ ions in the HCl solution: mol (H+ ) = Volume (H+ ) x Concentration (H+ )

2. Calculate the moles of OHions neutralized by the H+ ions in the titration: mol (H+ ) = mol (OH- ) at the equivalence point

3. Then, calculate the concentration of the OH- ions: Concentration (OH- ) = mol (OH- ) / Volume (OH- ) used* *Use either the volume of Ca(OH)2 from your best trial, or average the three best trials and use this average volume of Ca(OH)2.

4. Using the concentration of OH- calculated in #3 above, calculate the Ca2+ concentration and the Ca(OH)2 concentration (remember that 1 mole of Ca2+ ions and 2 moles of OHions are produced for every 1 mole of Ca(OH)2 dissolving!)

5. Substitute the concentrations of Ca2+ and OH- calculated above into the Ksp expression, and calculate the value of Ksp. Ksp = [Ca2+][OH- ] 2

concentration of HCl is 0.05

Answer 1