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

نویسندگان

  • Ali Asghar Jamali Department of Chemistry, Razi University, Kermanshah, I.R. IRAN
  • Mohammad Mahdi Khodaei Department of Chemistry, Razi University, Kermanshah, I.R. IRAN
چکیده مقاله:

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

دوره 18  شماره 2

صفحات  55- 59

تاریخ انتشار 1999-11-01

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