BULK PROPERTIES OF THE AQUEOUS SOLUTIONS OF BARIUM CHLORIDEN. D. Azizov UDC 541.135 Experimental investigations of the density of the aqueous solutions of BaCl2 at temperatures of 298-573 K and pressures up to 40 MPa have been carried out with the method of a constant-volume piezometer. The error of experimental data does not exceed 0.06%. The equation of state has been composed and the coefficients of thermal expansion and isothermal compressibility and the partial molar volumes of the electrolyte have been calculated on its basis. Azerbaijan State Petroleum Academy, Baku, Azerbaijan. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 76, No. 2, pp. 182-186, March-April, 2003. Original article submitted July 10, 2002; revision submitted September 25, 2002.