spectrophotometric determination of acidity constants of some anthraquinone derivatives in methanol-water mixtures

نویسندگان

mohammad mahdi khodaei

ali asghar jamali

چکیده

a spectrophotometric method is used to determine the acidity constants of some derivatives of 9,10-anthraquinone in binary methanol-water mixtures at 25 °c. there is a linear inverse relationship between pka of all acids and the mole fraction of methanol in the mixed solvent. the influence of substituents in the molecular structure on the ionization constants is discussed.

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Spectrophotometric Determination of Acidity Constants of Some Anthraquinone Derivatives in Methanol-Water Mixtures

A spectrophotometric method is used to determine the acidity constants of some derivatives of 9,10-anthraquinone in binary methanol-water mixtures at 25 °C. There is a linear inverse relationship between pKa of all acids and the mole fraction of methanol in the mixed solvent. The influence of substituents in the molecular structure on the ionization constants is discussed.  

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عنوان ژورنال:
iranian journal of chemistry and chemical engineering (ijcce)

ناشر: iranian institute of research and development in chemical industries (irdci)-acecr

ISSN 1021-9986

دوره 18

شماره 2 1999

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