This standard specifies a method for the determination of acetic acid content in Eletroplating black chromium solution by potential Titrimetric method. It is suitable for the determination of acetic acid content in Eletroplating black chromium solution. Measurement range is 2~ 10 g/L. The principle of the method is to separate lead nitrate and sodium sulfate settling to form a mixed solution of strong acid and weak acid. Potentiometric titration, poten-tiometry are performed using Glass electrode and saturated Calomel electrode. Titration to neutralize strong acid when pH value is 4.0, and continue titration to neutralize acetic acid when pH value is 9.0. The required reagents include lead nitrate solution, sodium sulfate solution and sodiumhydrate standard titration solution.