Thermodynamic function of valineacid in n-n dimethyl formamide mixtures from conductance measurement

Some physical properties enthalpy (ΔH), entropy (Δs), free energy (ΔG),capacities(Δcpₒ) and Pka values) for valine in dimethyl foramideover the temperature range 293.15-318.15K, were determined by direct conductance measurements. The acid dissociation at six temperature was examined at solvent composition x2) involving 0.141 of dimethyl foramide . As results, calculated values have been used to determine the dissociation constant and the associated thermodynamic function for the valine in the solvent mixture over temperatures in the range 293.15-318.15 k. The Pka1, and Pka2 were increased with increasing temperature.