OMB Meeting Book - Jan. 11, 2018

2016.03 (Nov. 2017) - Chlor-02/04 Final Action Review FOR ERP USE ONLY DO NOT DISTRIBUTE

(j) Potassium nitrate, (KNO 3 ), for analysis EMSURE® ISO,Reag, Ph. Eur., MERCK, # 105063 or equivalent.

(k) Acetone, for cleaning of the electrode, Honeywell, # 010-4, (Muskegon, MI, USA) or equivalent.

(l) Dimethylpolysiloxane, defoaming agent, Sigma-Aldrich, #DMPS2C or equivalent.

D.

Solutions

(a) Standardized silver nitrate (AgNO 3 ) solution, c = 0,1 mol/l.

If ready-to-use AgNO 3 standard solution (C. g) is not available, then weigh 16,9890 g ± 0,0005 g AgNO 3 (C. c) previously dried for 2 h at 120 °C ± 2 °C. Dissolve in water and make up to the mark in a 1000 ml volumetric flask. Store in a brown reagent bottle. After preparation, check the titer by titration of 5.0 ml with exactly 0.1 mol/l NaCl (C. h, or D. b). solution. For either commercial or in-house solution verify the titer on a regular basis following Formula 1 or 2 in Section I. If outside 0.095-0.105 mol/L investigate. The standardized AgNO 3 solution shall be protected from light, and can be stored for up to 2 months.

(b) Sodium chloride solution, c = 0,1 mol/l.

If ready-to-use NaCl (C. h) standard solution is not available, weigh 5,8440 g ± 0,0005 g NaCl (C. b), previously dried for 2 h at 110 °C ± 2 °C. Dissolve in water and make up to the mark in a 1000 ml volumetric flask. This solution is stable for up to 1 month.

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