RAPID SPECTROPHOTOMETRIC DETERMINATION OF WATERSOLUBLE MANGANESE IN SOILS USING 2-5BROMO-2PURIDYLAZO-5DIETHYLAMINOPHENOL
- Resource Type
- Article
- Authors
- QIU, XING-CHU; ZHANG, YU-SHENG; ZHU, YING-QUAN
- Source
- Soil Science; December 1984, Vol. 138 Issue: 6 p432-435, 4p
- Subject
- Language
- ISSN
- 0038075X; 15389243
This paper reports a spectrophotometric method for determining water-soluble manganese in soils. 2-(5-Bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) is used as a chromophoric reagent. It reacts with manganese in H2O – EtOH medium of PH 8.5 to form a purple complex having an absorption maximum at 558 nm and molar absorptivity of 1.06 × 105L-mol-1.cm-1. Beer's law is obeyed in the concentration range of 0 to 10 ±g of manganese per 25 ml of solution.