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(b)  Calculate chloride content in the sample, and report to three significant digits .— = × × × × ( / 100 ) 35.45 ( ) 100 2 - 0 CL mg g c V V f m where CL is the chloride content (mg/g); m is the sample weight (g); c is the certified concentration of silver nitrate titrant [0.1000 mol/L or standardized concentration; I ( a )]; V 2 is the AgNO 3 volume (mL) consumed at titration end point; V 0 is the AgNO 3 volume (mL) consumed at titration end point for Blank, G ( d ); f is the dilution factor for preparation of reconstituted powder, RTF, or concentrate [for samples requiring protein precipitation, F ( a )–( c ), an additional factor (e.g., for a 25 g sample, f = 2) will be needed]; 35.45 is the chloride weight (μg) corresponding to 1 mL 1 mol/L AgNO 3 ; and 100 is the mass conversion to milligrams/100 g. Under the repeatable analysis condition, the absolute difference between two independent test results should not exceed 2% of the arithmetic mean. References: (1) GB/T 601-2002 (2002) Chemical reagent–

Preparation of standard volumetric solutions, http:// www.chinesestandard.net/PDF-English-Translation/ GBT601-2002.html

J. AOAC Int . 99 , 1113(2016) DOI: 10.5740/jaoacint.16-0123 AOAC SMPR 2014.015 J. AOAC Int . 98 , 1079(2015) DOI: 10.5740/jaoac.int.SMPR2014.015

Posted: September 7, 2016

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