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Determination of the Dissociation Constant of Some Substituted Phenols by Potentiometric Method in Acetonitrile-Water Mixtures

Bazı Substitue Fenollerin Ayrışma Sabitlerinin Asetonitril-Su Karışımlarında Potansiyometrik Metotla Tayini

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Abstract (2. Language): 
The dissociation constants of phenol, 2-methylphenol, 3-methylphenol, 4-methylphenol, and 4-ethylphenol have been determined by potentiometric titration in a electrochemical cell with glass electrode at 25 oC in water and in the mixtures of acetonitrile and water where the following volume fractions (before mixing) of acetonitrile were used: 0.10, 0.20, and 0.30. The ionic strength of the solutions was adjusted to be 0.1 mol dm-3 using KCl. The dissociation constants were calculated by using the commercial Hyperquad 2008 program. The obtained results are in good concordance withliterature values.
Abstract (Original Language): 
Fenol, 2-metilfenol, 3-metilfenol, 4-metilfenol ve 4-etilfenol'ün ayrışma sabitleri %10-20-30 oranlarında hazırlanan asetonitril -su karışımında 25 oC potansiyometrik olarak elektrokimyasal hücrede elektrot ile tayin edilmiştir.Titrasyon çözeltilerinde iyonik şiddet KCl kullanılarak 0.1 mol dm-3 olarak ayarlanmıştır. Ayrışma sabitleri ticari bir program olan Hyperquad 2008 ile hesaplanmıştır. Elde edilen sonuçlar literatürdeki değerlerle uyumluluk göstermektedir.
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REFERENCES

References: 

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SDU Journal of Science (E-Journal), 2010, 5 (1): 60-66
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Hakan Aktaş email: ahakan@fef.sdu.edu.tr

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