start-ver=1.4 cd-journal=joma no-vol=9 cd-vols= no-issue=6 article-no= start-page=817 end-page=820 dt-received= dt-revised= dt-accepted= dt-pub-year=1993 dt-pub=19931210 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Color Development Based on the Ion Association of Molybdophosphate with Cationic Dye Chloro-Malachite Green en-subtitle= kn-subtitle= en-abstract= kn-abstract=Color development based on the ion association of molybdophosphate with a cationic dye, a chloro derivative of Malachite Green (Cl-MG), was investigated in an aqueous acidic solution. Cl-MG is very stable as its quinoid form in an acidic medium, and can easily react with molybdophosphate to form a green ion associate, which shows maximum absorption at 685nm. The experimental conditions for optimum color development have been examined. This color development reaction could be applied to the determination of trace amounts of orthophosphate. The molar absorptivity was 1.3×105dm3 mol-1cm-1 at 685nm. en-copyright= kn-copyright= en-aut-name=MotomizuShoji en-aut-sei=Motomizu en-aut-mei=Shoji kn-aut-name=本水昌二 kn-aut-sei=本水 kn-aut-mei=昌二 aut-affil-num=1 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=HagiwaraTakayuki kn-aut-sei=Hagiwara kn-aut-mei=Takayuki aut-affil-num=2 ORCID= en-aut-name= en-aut-sei= en-aut-mei= kn-aut-name=YokoyamaAtsushi kn-aut-sei=Yokoyama kn-aut-mei=Atsushi aut-affil-num=3 ORCID= en-aut-name=OshimaMitsuko en-aut-sei=Oshima en-aut-mei=Mitsuko kn-aut-name=大島光子 kn-aut-sei=大島 kn-aut-mei=光子 aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 affil-num=4 en-affil= kn-affil=岡山大学 en-keyword=Color development kn-keyword=Color development en-keyword=ion association kn-keyword=ion association en-keyword=molybdophosphate kn-keyword=molybdophosphate en-keyword=chloro-Malachite Green kn-keyword=chloro-Malachite Green END