Complex Formation of Crown Ethers and Cations in Water−Organic Solvent Mixtures: The Thermodynamic Functions of Complex Formation of Benzo-15-crown-5 with Na⁺ in Water + Ethanol at 298.15 K

Abstract

The enthalpies of solution of benzo-15-crown-5 ether in ethanol + water and ethanol + water + sodium iodide systems have been measured at T ) 298.15 K. The values of standard enthalpies of solution of benzo-15-crown-5 ether are positive in the mixtures of water and ethanol within the whole range of mixture composition. The equilibrium constants of complex formation of benzo-15-crown-5 ether with a sodium cation have been determined by conductivity measurements at T ) 298.15 K. In the process of complex formation, ethanol molecules show their hydrophobic properties.