User:Enalumenya/Temp/Solubility product.doc

PRACTICAL CHEMISTRY

Determination of solubility product of calciumhydroxide and then solubility of calciumhydroxide in sodiumhydroxide solution.

You are provided with the following:

FA1, which is 0.05M Hydrochloric acid;

FA2, which is sodiumhydroxide solution;

Solid P, which is calciumhydroxide.

You are required to determine the solubility product of calciumhydroxide and then the solubility of calciumhydroxide in sodiumhydroxide solution at room temperature.

Procedure

1. Weigh about 2.5g of P and add 250cm³ of water in a conical flask. Boil the mixture for about 5 minutes and then cool under the tap to room temperature. Filter the mixture and keep the filtrate for subsequent analysis.

Pipette 25cm³ of the filtrate into a clean conical flask and titrate with FA1 using phenolphthalein as indicator.

Repeat the titration two times and record your results in the table below.

Results

Mass of tube + P/g
Mass of tube/g
Mass of P/g

Volume of pipette used = ………………….. cm³

Burette reading	1	2	3
Final reading/cm3
Initial reading/cm3
Volume used/cm3

Average volume =

1. Weigh about 2.5g of P and add 250cm³ of FA2 in a conical flask. Boil the mixture for about 5 minutes and then cool under the tap to room temperature. Filter the mixture and keep the filtrate for subsequent analysis.

Pipette 25cm³ of the filtrate into a clean conical flask and titrate with FA1 using phenolphthalein as indicator.

Repeat the titration two times and record your results in the table below.

Results

Mass of tube + P/g
Mass of tube/g
Mass of P/g

Volume of pipette used = ………………….. cm³

Burette reading	1	2	3
Final reading/cm3
Initial reading/cm3
Volume used/cm3

Average volume =

Questions (Ca = 40, O = 16, H = 1)

1. Determine: (a) the solubility product of P.

(b) the solubility of P in g/dm³ in FA2.

1. Comment on your answer in (b) above.