Molecular Interaction Studies of Some α-Amino Acids in Aqueous NaOH Solutions from Ultrasonic Velocity Measurements

Apparent molal compressibilities (φ_K) and apparent molal volumes (φ_V), of L-serine, L-arginine and Lphenylalanine in aqueous sodium hydroxide solutions (0.0-0.10 mol kg^–1) at 303.15 K have been determined from precise density and ultrasonic velocity measurements. Limiting apparent molal compressibilities (φ_K^O), limiting apparent molal volumes (φ_V^O) and their constants (S_K,S_V) of these amino acids at infinite dilution were evaluated. Transfer adiabatic compressibilities (Δφ_K^O) and transfer volumes (Δφ_V^O) at infinite dilution from water to aqueous sodium hydroxide solutions have been calculated. These derived parameters have been interpreted in terms of ion-solvent and ion-ion interactions in the studied solutions.