title: Spectrophotometric determination of molybdenum with 7,8-dihydroxy-4-methylcoumarin and cetyltrimethylammonium bromide.
abstract: The 1:2 complexes formed between molybdenum and 7,8-dihydroxy-4-methylcoumarin in the presence and absence of cetyltrimethylammonium bromide (CTAB) have been studied. The binary complex formed at pH 5.6-6.0 in the absence of CTAB exhibits an absortion maximum at 360 nm with a molar absorptivity of 5.1 x 10(4) 1.mole(-1).cm(-1). The complex formed at pH 4.8-6.0 in the presence of CTAB has a molar absorptivity of 1.32 x 10(5) 1.mole(-1).cm (-1) at 400 nm, the wavelength of maximum absorption. Optimum conditions for complex formation were investigated and a rapid, sensitive and relatively selective method for the determination of up to approximately 70% of Mo in diverse alloys and steels is described. Small amounts of zirconium and tungsten interfere.
authors.affiliation: Department of Chemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt.
authors.forename: M T
authors.initials: MT
authors.lastname: Zaki
authors.forename: A K
authors.initials: AK
authors.lastname: Abdel-Kader
authors.forename: M M
authors.initials: MM
authors.lastname: Abdalla