Partial molal volumes of transfer of some amino acods from water to aqueous 1,4-dioxane solutions at 298.15 K

摘要

Apparent molal volumes of glycine, DL-a-alanine , L-valine, L-leucine and L- phenylalanine in water and in 2.5, 5, 10, 20, 25% aqueous solutions of 1,4-dioxane have been obtained from densities of their solutions at 298.15 K measUred by using precise vibrating tube digital densitymeter. The estimated partial molal volumes ( V_2~0) at infinite dilution have been used to obtain corresponding transfer volumes ( V °_(2"tr) ) from water to different 1,4-dioxane-water mixtUres which have been found to be positive for glycine, and both positive and negative for the remaining amino acids over the 1,4-dioxane concentration range studied. The data have been interpreted in terms of solute-cosolute interactions. Concentration dependent behavioUr of 1,4-dioxane in aqueous solutions have also been taken into account while interpreting the V °_(2,tr) values of amino acids.