Standard No.:	GB 7472-1987
Chinese Name:	水质 锌的测定 双硫腙分光光度法
English Name:	Water quality; Determination of zinc; Spectrophotometric method with dithizone
Professional Classification:	Z16 Analysis methods for toxic substances in water
Professional Classification:	GB National Standard
Issued by:
Issued on:	1987-03-06
Implemented on:	1987-08-01
Status:	VALID
Language:	English
File Format:	PDF
Word Count:	2500 words
Price(USD):	75 (USD)
Delivery:	via email in 1-3 business day

1 Application Scope

1.1 Determination substance: this standard specifies determination of zinc in water by spectrophotometric method with dithizone.
1.2 Sample type: this method is applicable to determination of trace zinc in natural water and some waste water. Relevant interference problems are detailed in Appendix A.
1.3 Scope: this method is applicable to determine water sample with zinc concentration of 5~50μg/L.
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 5μg/L.
1.5 Sensitivity: in this method, carbon tetrachloride is used for extraction, when the measurement is carried out at the maximum light absorption wave length of 535nm, the molar absorbance is about 9.3×104L/mol?cm.

2 Definition

As specified in this standard, total zinc content in the water sample shall be determined after the water sample is subject to acid digestion treatment.