Question

To prepare a buffer solution of ph 4.04 amount of barium acetate to br added to 100 ml of 0.1 ] acetic acid

Answer 1

It is imposible to prepare a buffer with pH 3 from acetic acid, or from its mixture with sodium acetate, regardless their ratio or concentrations. The reason is low dissociation constant of CH3COOH, aproximately equal to 1.8 x 10-5 . Off more, sodium acetate dissolved in water is hydrolyzed to NaOH /strong base/ and CH3COOH /weak acid/, and pH of its solution is over 7.

Best regards.

Note: you should rather use a mixture of 0.1M citric acid /a/ with 0.2M Na2HPO4 /b/ . Mix 15.89 ml of solution /a/ with 4.11 ml of solution /b/. The pH in this case is 3.00 in temperature interval from 15 to 30 oC.