title: Spectrophotometric determination of copper in alloys using naphthazarin.
abstract: Naphthazarin (5,8-dihydroxy-1,4-naphthoquinone; Naph) is proposed as a chromogenic reagent for the spectrophotometric determination of copper(II). The polynuclear complex has a mole ratio of Cu:Naph=4:6 in a 50% v/v ethanol/water medium containing 0.1 M ammonium acetate and 1.5% (w/v) sodium dodecyl sulfate. The copper-naphthazarin complex shows an absorption maximum at 330 nm with a molar absorptivity of 1.84x10(4) l mol(-1) cm(-1). Beer's law is obeyed up to 4.5 ppm of copper(II). The method was applied for copper determination in alloy samples with satisfactory results.
authors.affiliation: Department of Chemistry, Faculty of Science, Silpakorn University, Nakorn Pathom 73000, Thailand.
authors.forename: R
authors.initials: R
authors.lastname: Chaisuksant
authors.forename: W
authors.initials: W
authors.lastname: Palkawong-Na-Ayuthaya
authors.forename: K
authors.initials: K
authors.lastname: Grudpan