Dielectric relaxation studies of binary mixtures of N-methylacetamide and N, N-dimethylacetamide in benzene solutions using microwave absorption data

Abstract

Single frequency concentration variational method of Gopala Krishna, Trans Faraday Soc, 33 (1957) 767., has been used to determine the dielectric relaxation times() and the dipole moments(μ) of dilute solution of N-methylacetamide(NMA), N,N-dimethylacetamide(DMA) and NMA+DMA binary mixtures in benzene solutions at 25, 30, 35C and 40ºC by the standard standing wave techniques at 9.90GHz. Energy parameters (ΔH, ΔF, ΔS) for the dielectric relaxation process of NMA+DMA binary mixtures containing 30% of DMA have been calculated at 25, 30, 35 and 40ºC. Comparison has been made with the corresponding energy parameters for viscous flow. From the observations, it is found that the dielectric relaxation process like the viscous flow process can be treated as the rate process. On the basis of above studies, solute-solute and solute-solvent types of the molecular associations have been predicted.