DEVELOPMENT OF A SPECTROPHOTOMETRIC METHOD FOR DETERMINATION OF IONS Cu (II) WITH N- (2-HYDROXYBENZOYL) -N '- (p-TOSIL) HYDRAZINE IN AMMONIA MEDIA
A spectrophotometric method for the determination of Cu (II) ions with N- (2-hydroxybenzoyl) -N '- (p-tosyl) hydrazine (GBSH) in ammonia media has been developed. The optimal conditions for the formation of a complex compound have been found: pH of complexation; optimal time for color development; the amount of photometric reagent. Under optimal conditions of complexation of GBSG with Cu (Ⅱ) ions (λ = 401 nm, pH = 9.2, τ = 30 minutes, VGBSG = 3.75 ml), a calibration graph is constructed. The Bouguer-Lambert-Beer law is fulfilled in the range from 0.13 to 1.59 mg Cu (II) / 25 ml. The true molar light absorption coefficient of the complex compound of HBSG with Cu (Ⅱ) ions in the ammonia medium was 1480. The molar ratios in the solution of the complex compound - [Cu (Ⅱ)]: [HBSG] = 1: 1 were determined by saturation, equilibrium shift and conductometric titration. According to Babko's method, the conditional constant of stability of the GBSG complex with Cu (Ⅱ) ions was calculated and it was - 4.531016. The convergence and correctness of the developed spectrophotometric technique were determined by the method of mathematical statistics.