Standard No.:	GB 7471-1987
English Name:	Water quality - Determination of cadmium - Spectrophotometric method with dithizone
Chinese Name:	水质 镉的测定 双硫腙分光光度法
Chinese Classification:	Z16    Analysis methods for toxic substances in water
Professional Classification:	GB    National Standard
Source Content Issued by:	AQSIQ
Issued on:	1987-3-6
Implemented on:	1987-8-1
Status:	valid
Target Language:	English
File Format:	PDF
Word Count:	3000 words
Translation Price(USD):	60.0
Delivery:	via email in 1 business day

1 Application Scope 1.1 Determination substance: this standard specifies determination of cadmium in water and waste water by spectrophotometric method with dithizone. 1.2 Sample type: this standard is applicable to determination of trace cadmium in natural water and waste water. Relevant interference problem is detailed in Appendix A. 1.3 Scope: this method is applicable to determination of cadmium with the concentration range of 1~50μg/L; when concentration of cadmium is greater than 50μg/L, the sample is properly diluted before determination. 1.4 Detection limit: when the cuvette with optical path length of 20mm is used and the volume of the test portion is 100ml, the detection limit is 1μg/L. 1.5 Sensitivity: in this method, chloroform is used for extraction, when the measurement is carried out at the maximum light absorption wave length of 518nm, molar absorption coefficient is 8.56×104L/mol•cm. 2 Definition As specified in this standard, total cadmium content in the water sample shall be determined after the water sample is subject to acid digestion treatment.

Contents 1 Application Scope 2 Definition 3 Principle 4 Reagent 5 Apparatus 6 Sampling and Sample 7 Procedures 8 Expression of Results Appendix A (Supplement) Interfering Substance Appendix B (Informative) General Explanation for This Standard Additional Explanation