Mixing the chelating reagent B with Ni(II) forms the highly colored NiB22+, whose solutions obey Beer's law at 395 nm over a wide range. Provided the analytical concentration of the chelating reagent exceeds that of Ni(II) by a factor of 5 (or more), the cation exists, within the limits of observation, entirely in the form of the complex. Use the accompanying data to evaluate the formation constant kt for the process
