Simultaneous second derivative spectrophotometric determination of nickel(II) and copper(II) using diacetylmonoxime isonicotinoyl hydrazone

A derivative spectrophotometric method, based on the use of second-derivative absorption spectra, has been developed for the simultaneous determination of nickel(II) and copper(II) in aqueous medium using diacetylmonoxime isonicotionyl hydrazone (DMIH). The reagent gives intense colour reaction with nickel(II) and copper(II) in basic medium: The zero-order spectrophotometric method for the determination of these metal ions has been developed in aqueous medium. The molar absorptivity and Sandell's sensitivity for nickel(II) and copper(II) are 1.75 x 10(4); 1.12 x 10(4) lit. mol(-1) cm(-1) and 0.00335, 0.00565 mug of metal/cm(2) respectively. Beer's law is obeyed in the range 0.235-2.35 and 0.25-2.54 mug/ml for Ni(II) and Cu(II) respectively. The proposed simultaneous method involves the use of peak-to-base line measurement techniques.