Department of Chemistry, Himachal Pradesh University, Summer Hill, Shimla-171 005, Himachal Pradesh, India Manuscript received 24 December 2008, accepted 24 March 2009 Molar volume, viscosity and conductance of ascorbic acid in water, 0.01 m aqueous sodium chloride and 2, 4 and 6 wt. % of dextrose in 0.01 m aqueous sodium chloride solutions have been evaluated from density, viscosity and conductance data respectively at temperatures 303.15, 308.15, 313.15 and 318.15 K. The solute-solvent

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... tions for ascorbic acid in water, 0.01 m aqueous sodium chloride and 2, 4 and 6 wt. % of dextrose in 0.01 m aqueous sodium chloride have been inferred from Φov, B-coefficient of Jones-Dole equation and Amo values. The structure making/ breaking behaviour of ascorbic acid is inferred from the sign of [∂2 Φov/∂T2]p, DB/DT transition state theory i.e. free energy contribution per mole of solute (∆µ2) and free energy contribution per mole of solvent (∆µ1) values and temperature coefficient of Walden product i.e. d(Amoηo)/dT. It has been found from viscosity and conductance studies that ascorbic acid behaves as structure-breaker in water. 0.01 m aqueous sodium chloride and 2, 4 and 6 wt. % of dextrose in 0.01 m aqueous sodium chloride solutions. The energy of activation for ascorbic acid in different systems has also been calculated from conductance and viscosity data.