1956 年 76 巻 6 号 p. 689-693
The flame intensity of the potassium ion in mineral water, when the mineral water is directly submitted to flame photometry, at 768 mμ is either lessened or intensified by phosphate, sulfate, or sodium ion. This potassium ion was found to be determined by treating mineral water with R-Cl type resin, Amberlite IRA-410, to exchange all the anions in the water with chlorine ion, adding sodium ion to bring its content to a definite level (Na+ content: 500 p. p. m.), and by comparison with the calibration curve of the standard solution (K+ with 500 p. p. m. Na+ as its chloride). This method of determination was not affected by other components, such as Ca2+, Mg2+, Al3+, and Fe3+. Discussion on acid mineral water will be made in subsequent reports.