Title: Simultaneous Determination of Nitrate and Iodide Ions in Aqueous Solutions by Dual-wavelength Spectrophotometry
Abstract: Nitrate and iodide ions are usually coexisted in environmental and food samples. When the contents of nitrate or iodide ions are determined directly using UV spectrophotometry, the interference between the two kinds of ions will occur. Therefore, in this study, isobestic point dual-wavelength spectrophotometry with primary and secondary wavelengths of 220.0 and 231.5 nm was used to simultaneously determine trace nitrate ions and coexisting iodide ions in solutions. When the nitrate concentration is in the range of 0~0.12 mmol/L, and the iodide concentration is in the range of 0~0.10 mmol/L, there is a liner relationship between absorbance difference A220-231.5 and nitrate concentration CNO-3which can be described by the equation of A220-231.5= 2.9958CNO-3+0.0016 (R2=0.99994). Iodide ion concentration can be indirectly detected based on the additivity of the absorbance described by the equations of A220 (I-)=A220- A220 (NO3-) = 10.7394CI-+0.0029(R2=0.99994) and A220(NO3-)=3.6099CNO-3+0.0084(R2= 0.99994). The relative standard deviation of the analysis method is 0.6% for nitrate ion and 0.2% for iodide ion, and the recovery is 99.5%~102% for nitrate ion and 99.9%~100% for iodide ion, respectively. The method was proved to be convenient and reliable for simultaneous determination of trace nitrate and iodide ions in aqueous solutions.
Publication Year: 2011
Publication Date: 2011-01-01
Language: en
Type: article
Access and Citation
Cited By Count: 1
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot