Analytical study of non-aqueous solutions of crown ethers complexes by conductivity

الملخص EN

The conductivity of NaCl, KC1 and RbCl in ethanol has been studied in absence and presence of crown ethers 12C4,15C5,18C6 and DC18C6.

The stability constant "logK" of the resulting 1:1 complexes between cations (Na+, K+ and Rb+) with crown ethers were determined by molar conductivity-mole ratio data.

The order of logK values for Na+ DC18C63 18C6> 15C5, K+ DC18C6> 18C6> 15C5> 12C4 and Rb+ 18C6> DC18C6> 15C5> 12C4.

The thermodynamic formation of complexation were determined, it reflects the tight association between cation and donor atoms of crown ethers.

The solvent effect was also studied and results revealed that this effect follow the dielectric constant of solvent.