
%0 Journal Article
%A Goyal, SS 
%A Tandon, JP 
%T Spectrophotometric studies of chelate formation of lanthanum and thorium with picramine azo dyes
%J Australian Journal of Chemistry
%D 1968/10/01
%V 21
%N 10
%P 2433-2436
%K 
%R https://doi.org/10.1071/CH9682433
%U https://www.publish.csiro.au/paper/CH9682433 
%X 0,O'-Dihydroxypicramine azo dyes form water-soluble yellowish pink complexes with thorium and lanthanum in the pH ranges 1.5-4 and 6-9 respectively. The compositions of the complexes determined by continuous variations and molar ratio methods were found to be 1 : 2 in thorium-Picramine CA and 1 : 1 in lanthanum-Picramine R systems. The order of the formation constant of thorium-Picramine CA complex is 1011 and that of lanthanum-Picramine R is 105. The free energy changes of formation are also calculated. 
