Solvent extraction and photometric determination of a microgram of cerium with N-p-tolyl-p-chlorobenzohydroxamic acid

A spectrophotometric method for determination of a microgram quantity of cerium with N-p-tolyl-p-chlorobenzohydroxamic acid is described. The orange-red-colored complex is extracted from chloroform at pH 9 which absorbs between 460 and 465 nm. Beer's law is obeyed at this wavelength. A clean-cut separation from many commonly occurring metal ions is easily accomplished. The system obeys Beer's law within the range of 0.5–28 ppm of cerium(IV). The molar absorptivity of cerium-N-p-tolyl-p-chlorobenzohydroxamic acid complex is 4.5 × 10³ liters mol^?1 cm^?1.