|关键词: 分光光度法 磷 酸度 pH指示剂
|Exploration on the Effect of the Colorred-Solution Acidity in Determining Total Phosphorus in Soil by Molybdenum Antimony Anti Spectrophotometry
WANG Wen lu
Gansu Environmental Monitoring Center, Lanzhou, Gansu 730020, China
|When using the alkali fusion molybdenum antimony anti spectrophotometric method for the determination of total phosphorus in soil, several problems were present including the influence of solution acidity on the formation and stability of the phosphorus molybdenum complex, difficulty in making the pH indicator 2,4 dinitrophenol at low ambient temperature and the coloration was not obvious for identification. This paper studied the effect of the acidity of the colorred solution on the absorbance value and improved preparation method for the 2, 4 dinitrophenol indicator. The modified method is simpler in operation and more accurate in analysis.
|Key words: Spectrophotometric method Phosphorus Acidity pH indicator