AOAC Official Method 941.13 Chlorides (Total) in Prepared Mustard Titrimetric Method

Titrimetric Method
First Action 1941
Final Action

Weigh 3–4 g test portion from weighing bottle, place in 300 mL Erlenmeyer, and add excess standard 0.1M AgNO3 (usually 30 mL is enough). Mix thoroughly, add 15 mL HNO3, and bring to boil on hot plate. To boiling mixture add 15 mL 5% KMnO4 solution (w/v),5 mL at time, rotating flask after each addition to mix contents. Add ca 50 mL H2O and filter into 200 mL volumetric flask. Wash filter free of AgNO3 and dilute to volume with H2O. Mix thoroughly and titrate 100 mL aliquot with 0.1M KSCN, using 2 mL saturated ferric alum solution as indicator. Calculate chlorides as NaCl.

References: JAOAC 24, 703(1941); 25, 97(1942).
CAS-7647-14-5 (sodium chloride)