Theoretical Study of Thermodynamic Functions and Equilibrium Constant of Some Gum Arabic Mono Saccharide

Abstract

ABSTRACT The current research was under _ taken development and evaluation of thermodynamic parameters and equilibrium constant of some mono sugars fragment in Gum Arabic structure by using computational chemistry semi-empirical method (AM1) Mopac calculation . The results of studied sugars were obtained as follows for compound ( I ) : enthalpy change (∆H) 143.150 kJ mol-1 , entropy change (∆S) 1.331 kJ mol-1 , heat capacity at constant pressure (∆Cp) 0.836 kJ mol-1 , free energy change (∆G) - 253.373 kJ mol-1 , Helmholtz free energy (∆A) -253.373 kJ mol-1, internal energy change (∆U) 143.150 kJ mol-1 , chemical potential (µi) ـ253.373 kJ mol-1 , heat capacity at constant volume (∆Cv) 0.828 kJ mol-1, electrical work (Wele) - 253.373 kJ and equilibrium constant (K) 1.107 . The results for compound (II) : enthalpy change (∆H) 113.205 kJ mol-1 , entropy change (∆S) 1.098 kJ mol-1 , heat capacity at constant pressure (∆Cp) 0.6679 kJ mol-1 , free energy change (∆G( - 213.912 kJ mol-1 , Helmholtz free energy (∆A) - 213.912 kJ mol-1, internal energy change (∆U) 113.205 kJ mol-1 , chemical potential (µi) ـ213.912 kJ mol-1 , heat capacity at constant volume (∆Cv) 0.6595 kJ mol-1, electrical work (Wele) - 213.912 kJ and equilibrium constant (K) 1.090 . Compound (III) : obtained these results enthalpy change (∆H) 116.205 kJ mol-1 , entropy change (∆S) 1.1046 kJ mol-1 , heat capacity at constant pressure (∆Cp) 0.6807 kJ mol-1 , free energy change (∆G) - 212.979 kJ mol-1 , Helmholtz free energy (∆A) - 212.979 kJ mol-1 internal energy change (∆U) 116.205 kJ mol-1 , chemical potential (µi) ـ 212.979 kJ mol-1 , heat capacity at constant volume (∆Cv) 0.6724 kJ mol-1, electrical work (Wele) - 212.979 kJ and equilibrium constant (K) 1.089. All this result was taken at constant temperature and pressure . The results obtained the possibility of executed the operations of samples , simulation and application of computational chemistry in thermochemisrty.