Molecular interactions of 1,2-dihydroxyethyl-3,4-dihydroxyfuran-2-one in aqueous N-cetyl-N,N,N-trimethyl ammonium bromide solutions with reference to manifestation of solvation

Abstract

Apparent molar volumes ( ϕ v ) and viscosity B-coefficients for 1,2-dihydroxyethyl-3,4-dihydroxyfuran-2-one (ascorbic acid) in (0.001, 0.003, and 0.005) mol · dm −3 aqueous cetrimonium bromide (N-cetyl-N,N,N-trimethyl ammonium bromide) (C 19H 42BrN) solutions have been determined from solution density, ρ, and viscosity, η, measurements at T = (298.15, 308.15, and 318.15) K as a function of the concentration of ascorbic acid. Within the investigated temperature range, the relation: ϕ v 0 = a 0 + a 1 T + a 2 T 2 , hase been used to describe the partial molar volume ϕ v 0 . These results, in conjunction with the results obtained in pure water, have been used to calculate the standard volumes of transfer Δ ϕ v 0 and viscosity B-coefficients of transfer for ascorbic acid from water to aqueous cetrimonium bromide solutions for rationalizing various interactions in the ternary solutions. The structure making or breaking ability of ascorbic acid has been discussed in terms of the sign of ( ∂ 2 ϕ v 0 / ∂ T 2 ) P . An increase in the transfer volume of ascorbic acid with increasing cetrimonium bromide concentration has been explained by the Friedman–Krishnan co-sphere model. The activation parameters of viscous flow for the ternary solutions studied have also been calculated and explained by the application of transition state theory. The 3-D representation of the investigated molecules concerned with this paper is shown below for a better understanding. ▪