Abstract

DIFFERENTIAL THERMAL ANALYSIS AND PHYSICO-CHEMICAL PROPERTIES OF RUBIDIUM SOAPS IN ALKANOLS

Saroha SPS*, Mehrotra K† and Ganjewala D**

Abstract

Rubidium soaps (caprylate, caprate) exhibit exotherm and endotherm through differential thermal analysis. The Exotherm and endotherm indicate the crystallization, melting and decomposition states of these soaps ie there exist three temperatures, temperature of crystallization, melting and decomposition. The adsorption excess and surface area covered by 1 g mole micelle for Rubidium soaps in alkanols (methanol, butanol and pentanol) (3.75, 3.86); (4.46, 4.56); (5.62, 5.70 )10-10 cm 2 is calculated using Gibb’s adsorption equation. The difference in parachor of soap and solvent, P (soap-solven) K1 and that of solvent K2 is determined from Hammic and Andrews’ equation.

Keywords: Exotherm, adsorption, endotherm, soaps, crytallisation, melting, decomposition.