GB/T 9729-2007 in English

《GB/T 9729-2007化学试剂 氯化物测定通用方法》由TC63（全国化学标准化技术委员会）归口，TC63SC3（全国化学标准化技术委员会化学试剂分会）执行，主管部门为中国石油和化学工业联合会。

Chemical reagent - General method for the determination of chloride

1 Scope

This standard specifies the general methods for the determination of chloride by visual turbidimetry.

This standard is applicable to the determination of micro chloride in chemical reagents. The determination range is 0.2 μg/mL ~ 4 μg/mL (in Cl).

2 Normative references

The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments to (excluding corrections) to, or revisions of, any of these publications do not apply. However, parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. For undated references, the latest edition applies.

GB/T 602 Chemical reagent - Preparations of standard solutions for impurity (GB/T 602-2002, ISO 6353-1: 1982, NEQ)
GB/T 603 Chemical reagent - Preparations of reagent solutions for use in test methods (GB/T 603-2002, ISO 6353-1: 1982, NEQ)
GB/T 6682 Water for analytical laboratory use - Specification and test methods (GB/T 6682-1992, neq ISO 3696: 1987)

3 Principle

In nitric acid medium, chloride ions and silver ions generate insoluble silver chloride. When chloride ion content is low, silver chloride is suspended in a certain period of time, which makes the solution turbid and can be used for visual turbidimetric determination of chloride.

4 Reagents and materials

Foreword i
1 Scope
2 Normative references
3 Principle
4 Reagents and materials
5 Determination