Abstract: Satuiated solutions of five aromatic hydrocarbons of o-xylene, m-xylene, p-xylene, chlorohenzene and bromobenzene were prepared by circulation of the solute valour in closed system. At the same time solubilities of aromatic hydrocarbons were determined in a varity of silver nitrate solution with diffeient concentrations (ionic strength was adjusted to 1.00 by potassium nitrate solution). The formation constants of complexes produced by silver ion with the abave five aromatic hydrocarbons were calculated by actual solubility measured by using curve-fitting methed. The result are compared with the literature values.

Key words: Equilibrium solubilities, Xylene, Halogeno-Benzene, Silver nitrate solution, Solute vapour circulation, Complex formation constant