44. Solving a chemistry problem

15. The molar absorption coefficient of the Ni2 complex with dimethylglyoxime in solution is 2556 at a wavelength of 445 nm in terms of the nickel cation. Calculate the optimal concentration of the complex in mol/l, at which the relative systematic error of the photometric determination of the nickel concentration is the smallest. The thickness of the absorbing layer l= 1 cm.