Solubility of three types of benzamide derivatives in toluene, ethyl acetate, acetone, chloroform, methanol, and water at temperatures ranging from 288.15 to 328.15 K at atmospheric pressure

Abstract

The solubility of three types of benzamide derivatives S1, S2, and S3 in six pure solvents, with various polarities, including toluene, ethyl acetate, acetone, chloroform, methanol, and water at temperatures ranging from 288.15 to 328.15K (318.15K for acetone) was determined by ultraviolet spectrophotometry at atmospheric pressure. The solubility of S1, S2, and S3 in the selected solvents increased with the increase in temperature. The mole fraction solubility of S1 was found to be the highest in methanol (1.2464×103 at 328.15K) and the solubility of S1 in the selected solvents was in the following order: methanol>acetone>chloroform>ethyl acetate>toluene>water. The highest mole fraction solubility of S2 was found in chloroform (7.6750×103 at 328.15K) and the solubility of S2 in the six solvents followed the order: chloroform>methanol>acetone>ethyl acetate>toluene>water. However, for S3 the mole fraction solubility was found to be highest in acetone (1.1520×103 at 318.15K) and the order was acetone>methanol>ethyl acetate>chloroform>toluene>water. The experimental solubility data were correlated with the modified Apelblat equation, λh model, and ideal model. The calculated solubility by the three models showed good agreement with the experimental values and the modified Apelblat equation provided the best correlation results. Based on the solubility data, the dissolution enthalpy and entropy of S1, S2, and S3 were calculated by using the van't Hoff equation.