Determination of Sodium and Potassium Oxides by Flame Photometry in Portland Cement Raw Materials and Mixtures and Similar Silicates

Abstract

perature coefficients appear to be in qualitative agreement with the relative chemical reactivity of toluene, the xylenes, and benzene. CONCLUSIONSThe temperature coefficient of absorbance in the ultraviolet spectral region is a significant factor for certain aromatic hydrocarbons and some chelated aliphatic oxygenated compounds.Precise quantitative analyses of mixtures that contain any of these substances require control of the temperature of the sample, or empirical corrections for observed deviations in temperature. For the determination of other compounds noted herein, the variation of absorbance with temperature is usually negligible compared with the normal manipulatory errors.