Kinetic studies on 4d and 5d transition metal complexes. Part III. The kinetics of the reaction of azidopentamminerhodium(III) perchlorate with hydroxide ion

Abstract

The kinetics of the reaction [Rh(NH₃)₅N₃]²⁺+ OH^–→[Rh(NH₃)₅OH]²⁺+ N₃^– have been studied in the temperature range 77–98° by following spectrophotometrically the rates of disappearance of the complex ion and appearance of the azide ion. The ionic strength of the reacting solution was varied in the range 6–40 millimoles per litre of sodium hydroxide. There is no interference from the aquation. The results are in agreement with the Brønsted–Bjerrum theory of the primary salt effect at all temperatures. The second-order rate constants at zero ionic strength vary with temperature according to the equation k₂°(I.mole^–1 sec.^–1)= 7·361 × 10¹⁸ exp(–34,600)/RT.