Preparation of buffers

 PREPARATION OF ACETATE BUFFER

Aim

To prepare 0.1M acetate buffer of pH 4.

Procedure

Stock solution A : 0.2M solution of acetic acid 

Stock solution B : 0.2M solution of sodium acetate

 Mix 41 ml of A and 9ml of B and diluted to a total of 100ml using distilled water. Measure pH using pH meter.

A (ml)	B (ml)	pH
46.3	3.7	3.6
44	6	3.8
41	9	4
36.8	13.2	4.2
30.5	19.5	4.4
25.5	24.5	4.6
20	30	4.8
14.8	35.2	5
10.5	39.2	5.2
8.8	41.2	5.4
4.8	45.2	5.6

 Result

0.1  molar acetate buffer of pH 4 was prepared and confirmed by measuring pH using pH meter.

 

 PREPARATION OF CARBONATE BICARBONATE BUFFER

Aim

To prepare 0.1M carbonate and bicarbonate buffer of pH 10.

Procedure

Stock solution A : 0.2M solution of anhydrous sodium carbonate 

Stock solution B : 0.2M solution of sodium bicarbonate

Mix 27.5 ml of A and 22.5ml of B and diluted to a total of 100ml using distilled water. Measure pH using pH meter. Confirm the pH using pH meter.

A (ml)	B (ml)	pH
4	46	9.2
9.5	40.5	9.4
16	34	9.6
22	28	9.8
27.5	22.5	10
33	17	10.2
38.5	11	10.4
42.5	7.5	10.6

 Result

0.1 molar carbonate bicarbonate buffer of pH 10 was prepared and confirmed by measuring pH using pH meter.