A POTENTIOMETRIC STUDY OF SILVER COMPLEXES WITH SOME CROWN ETHERS IN BINARY ETHANOL-WATER MIXTURES

A potentiometric study concerning the interaction between silver ion and several crown ethers in different ethanol-water mixtures has been carried out at 25°C. The formation constants of the resulting 1:1 complexes were determined from the potentiometric data and found to vary in the order 18C6>15C5>DB18C6>DB30C10>B15C5>12C4>DB24C4. There is an inverse linear relationship between the logarithm of the formation constants and the mole fraction of water in the mixed solvent. The influence of a number of members in the macrocycle and of substituents in the polyether ring on the stability of the complexes is discussed.