The Pb2+ complexes with macrocyclic ligand 1,7,10,16. Tetraoxa 4, 13 diazac
iclooctadecan (Criptand [2.2])] were studied The stability-constants of the
studied complexes were determined by potentiometric methods which showed t
hat there is two complexes Pb2+-complexes [2,2], 1:1 and 1:2 (metal-ligand
ratio), that is formed. The stability of these complexes showed that cripta
nd [2,2] can be used as analitic reactiv for Pb2+ potentiometric determinat
ion.