Description
| - The spectrophotometric determination of phosphate based on the ion association komplex with Rhodamin B is H2PO4[Mo3O10] RhB . Linear calibration curves were observed for 1-7 10-6 M H2PO4- (max = 552 nm, e= 1,42 10-5 dm3 mol cm-1) in 1 M sulphuric acid in the presence of 0,01% non-ionic surfactant Brij 35 and 0,03 M sodium molybdate. The detection limits are XD = 12,4 ppb XD = 36,6 ppb (Graham), XDm = 24,4 ppb (Miller) or 25,6 ppb (IUPAC). No interferences at 1x10-4 M H2PO4- were observed for 1000:1 Mg2+, K+, Na+, NH4+, NO3-, SO42-, Cl-, HCO3- and 100:1 Al3+, Fe2+, Ca2+. As (III, V), NO2- and Si (IV) were especially tested as considerable interferents, from which As (III, V) and NO2- interfere above the concentration only which cannot be found in natural waters. The Si (IV) was masked with 0,1 g l-1 tartaric acid. The optimalised method was applied fot the determination of phosphate in drinking and surface water.
- The spectrophotometric determination of phosphate based on the ion association komplex with Rhodamin B is H2PO4[Mo3O10] RhB . Linear calibration curves were observed for 1-7 10-6 M H2PO4- (max = 552 nm, e= 1,42 10-5 dm3 mol cm-1) in 1 M sulphuric acid in the presence of 0,01% non-ionic surfactant Brij 35 and 0,03 M sodium molybdate. The detection limits are XD = 12,4 ppb XD = 36,6 ppb (Graham), XDm = 24,4 ppb (Miller) or 25,6 ppb (IUPAC). No interferences at 1x10-4 M H2PO4- were observed for 1000:1 Mg2+, K+, Na+, NH4+, NO3-, SO42-, Cl-, HCO3- and 100:1 Al3+, Fe2+, Ca2+. As (III, V), NO2- and Si (IV) were especially tested as considerable interferents, from which As (III, V) and NO2- interfere above the concentration only which cannot be found in natural waters. The Si (IV) was masked with 0,1 g l-1 tartaric acid. The optimalised method was applied fot the determination of phosphate in drinking and surface water. (en)
- Spektofotometrické microstanovenístanovení fosforečnanů založené na vzniku iontového asociátu s Rhodaminem B ve vodách. (cs)
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