THERMOCHEMICAL PROPERTIES OF ELECTROLYTE-SOLUTIONS IN 2-ALKOXYETHANOL-WATER MIXTURES

Dissolution enthalpies for NaCl in mixtures of water with 2-methoxyeth anol, 2-ethoxyethanol and 2-butoxyethanol at 298.15 K and for Nal in m ixtures of water with 2-butoxyethanol at 298.15 K and 308.15 K have be en measured. The standard solution enthalpies A(s)H degrees of the sal ts go through a maximum within the range of high water content. The po sition and the height of the maximum depend both on the nature of the salt and the size of the 2-alkoxyethanol molecule. It was concluded th at 2-alkoxyethanols in water are hydrophobically hydrated and that the ir hydration shell is weaker than that of alkanols. The mixtures of wa ter with 2-alkoxyethanols, when used as solvents for the electrolytes, exhibit some similarities in thermochemical properties both to water- alkanol mixtures and to mixtures of water with some aprotic solvents.