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Refractive indexes measurement and correlation for selected binary systems of various polarities at 25 0C

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: Teodorescu M., Secuianu C.

Editorial: Journal of Solution Chemistry, 42 (10), p.1912-1934, 2013.

Rezumat:

New refractive indexes at 25 0C were measured and reported here for 19 binary mixtures of pentan-3-one + 1,2-dichloroethane, + 1,3-dichloropropane, + 1,4-dichlorobutane, + trichloromethane, + 1,1,1-trichloroethane, + 1,1,2,2,-tetrachloroethane, cyclopentanone + 1-chlorobutane, + 1,1,2,2,-tetrachloroethane, cyclohexanone + 1,1,2,2-tetrachloroethane, 5-chloro-2-pentanone + n-hexane, + toluene, + ethylbenzene, nitromethane + trichloromethane and nitromethane or nitroethane, + 1,2-dichloroethane, + 1,3-dichloropropane, + 1,4-dichlorobutane. The experimental refractive index deviations have been evaluated and correlated with the consistent 3-parameters Redlich-Kister equation with good results. The molar refraction was also examined for the systems including pentan-3-one, cyclopentanone, cyclohexanone and 5-chloro-2-pentanone for which densities and excess molar volumes are available from previous works. Different theoretical (n-ro) mixing rules were tested for these systems, too. Excess Gibbs free energy GE and excess enthalpy HE values were considered together with the excess molar volumes VE, excess refractive indexes , molar refraction R and excess molar refractions RE on mixing in discussing the influence of the alkyl chain length or of the nature of the second component in the mixture in terms of molecular interactions.

Cuvinte cheie: Refractive index; molar refraction; n-ro mixing rules; ketone, cycloketone or chloroketone; chloroalkanes; nitroalkanes