Review Team (February 2016).pdf

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Under continuous stirring and without touching the electrode, titrate the sample solution 145
automatically with 0.1 M standardized silver nitrate solution [Ci], up to the end potential. The 146
consumption of 0.1 M of silver nitrate solution [Ci] should be recorded automatically and can be 147
read from the titrator software, or documented in the titrator operating records. For manual 148
titration, using a burette add 0.1 M standardized silver nitrate solution [Ci], until the end 149
potential has nearly been met. Then continue to titrate slowly until the end point is met as 150
observed by the two small (about 0.05 mL) silver nitrate solution. 151
152
(c) Special case: determination of very low amounts of chloride 153
When determining low chloride concentrations, like desalted whey powder, for greater precision 154
it is preferable to use a standardized 0.025 mol/L AgNO 3 [Dg] solution for the titration. 155
(d) Blank test: determination of reagent background content of chloride 156
Perform a blank test using reagents substituting water [Ca] for the sample portion. The titrant 157
consumption of the blank test obtained at the endpoint shall be less than 0.05 mL for using the 158
0.1M standardized silver nitrate and 0.2 mL for using the 0.02 M standardized silver nitrate. 159
Otherwise check the reagents and water involved into the procedures, and perform the blank test 160
again until the criteria is achieved. 161
162
H. System Suitability Test 163
Prior to use. 164
(a) Transfer 5 mL of NaCl solution [ Ch or D b] into a 120 mL sample beaker. 165
If 0.02 M AgNO3 titrant is required then use 1 mL NaCl solution.. 166
(b) Add 5 mL nitric acid solution [De] and 50 mL water. 167
(c) Place the washing solution [D f] in the washing position of the auto sampler, 168
(d) Titrate using an automatic, semi-automatic or manual titrator. 169
2015.07/2015.08 (February 2016)
Chlor-02/Chlor-04
FOR ERP USE ONLY
DO NOT DISTRIBUTE