AP Chemistry salt lab

Salt Hydrolysis 

When a salt is dissolved in water, the resulting solution may be acidic, basic or neutral.  You will use litmus paper to classify the solutions of several salts.

Safety:  Wear goggles and aprons.  Wash your hands at the conclusion of the lab.

Procedure: Read section 16.9 in text book. You will be testing copper(II) sulfate, sodium sulfate, sodium chloride, sodium carbonate, aluminium nitrate, iron(III) chloride, and sodium acetate. 

Put a small piece of blue litmus paper and a small piece of red litmus paper on a glass plate.  Transfer a drop of each solution to the test strips and record the results. (Note: Your data should be the color of both strips for each solution tested.)

Conclusion: For each solution: Is it acidic, basic or neutral  (A table would be nice here).

Questions:  1. Define hydrolysis.

2. Write an equation for the formation of each salt from its acid and its base.  Label each acid and base as strong or weak.  Did your test results match

                        a) your pre-lab predictions?

                                                b) the results predicted by considering the source acid and base?

3. List the steps for finding the pH of a solution of a particular salt (without going to the laboratory)?

Salt Hydrolysis Prelab                                              Name _________________________

1. Read section 16.9 in text book.

2. Fill in the blanks with weak/strong: 

                        a) A neutral salt is formed from a _____ acid and a _____ base.

                        b) An acidic salt is formed from a _____ acid and a _____ base.

                        c) A basic salt is formed from a _____ acid and a _____ base.

3. Predict: acidic, basic, or neutral salt solution.

a) copper(II) sulfate

b) sodium sulfate

c) sodium chloride

d) sodium carbonate

e) aluminium nitrate

f) Iron(III) chloride

g) sodium acetate