Partial molar volumes and adiabatic compressibilities of N-acetyl-DL-serinamide and N-acetyl-L-threoninamide in dilute aqueous solutions

Densities and sound velocities in dilute aqueous solutions of N-acetyl-DL-serinamide and N-acetyl-L-threoninamide were measured at 5, 15, 25, 35, and 45 degrees C. Partial molar volumes and partial molar adiabatic compressibilities of these amino acid derivatives at infinite dilution were determined. The partial molar quantities for the parent amino acids, serine and threonine, were also determined and compared with the acetyl amide derivatives. The contribution of the side chain of the N-acetyl amino acid amide or amino acid to the partial molar quantities were estimated from the difference between the partial molar quantities for the solute studied and those for the corresponding species, N-acetyl-glycinamide or glycine, without the side chain.