فهرس المقالات acid–base properties

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  1 - Determination of the acid dissociation constants of the p-sulphonato-calix[4]arene
  Monireh Hajmalek Mohammad Sajjad Khalili Karim Zare Omid Zabihi
  10.22034/jna.2014.01.007
  The acid dissociation constants of the hydroxyl groups in 25, 26, 27, 28-tetrahydroxy-5, 11, 17, 23-tetrasulphonic-calix[4]arene (SC4) were determined at 25οC by a combination of potentiometric and spectrophotometric titration method. The first and second acid d أکثر

  The acid dissociation constants of the hydroxyl groups in 25, 26, 27, 28-tetrahydroxy-5, 11, 17, 23-tetrasulphonic-calix[4]arene (SC4) were determined at 25οC by a combination of potentiometric and spectrophotometric titration method. The first and second acid dissociation constants (pKa1, pKa2) were found to be 3.19 and 12.1, which demonstrated pKa shift due to intramolecular hydrogen bonding interactions among hydroxyl groups in SC4. تفاصيل المقالة