Abstract: | Summary Chrom Red Brown 5 RD has been found as a sensitive reagent for the spectrophotometric determination of thorium. Concentrations as low as 1 g thorium/1 ml can be easily determined at wave length 485 nm. Sulphate, chloride, ferric and zirconium ions badly interfere, while Li, Na, K, Ni, Co, Cu2+, Cd, Ca, Mg and Cr3+ do not. U6+ and Ce4+ are permissible as traces.Part II: Zaki, M. R., and K. Shakir: Z. analyt. Chem. 177, 196 (1960). |