Yazdanipour, A. (2009). Study of protonation equilibrium of lorazepam by potentiometry and multiwavelengths spectrophotometry. Journal of the Iranian Chemical Research, 2(4), 293-297.
Ateesa Yazdanipour. "Study of protonation equilibrium of lorazepam by potentiometry and multiwavelengths spectrophotometry". Journal of the Iranian Chemical Research, 2, 4, 2009, 293-297.
Yazdanipour, A. (2009). 'Study of protonation equilibrium of lorazepam by potentiometry and multiwavelengths spectrophotometry', Journal of the Iranian Chemical Research, 2(4), pp. 293-297.
Yazdanipour, A. Study of protonation equilibrium of lorazepam by potentiometry and multiwavelengths spectrophotometry. Journal of the Iranian Chemical Research, 2009; 2(4): 293-297.
Study of protonation equilibrium of lorazepam by potentiometry and multiwavelengths spectrophotometry
Department of Chemistry, Faculty of Sciences, Islamic Azad University, Arak Branch, Arak, Iran
Abstract
The acid-base equilibrium of lorazepam was studied by means of potentiometry and multiwavelengths spectrophotometry. The stoichiometric equilibrium constants were determined at 25 °C and constant ionic strength 0.1 mol L-1 (NaCl). The acidity constants pK1=1.58±0.05 and pK2=11.67±0.07 were found by potentiometry, and pK1=1.54±0.02 and pK2=11.61±0.03 by multi-wavelengths spectrophotometry. Potentiometric determination of equilibrium constants was performed by application of the formation function method. Data analysis program applied for multi-wavelengths spectrophotometric determination of acidity constants.
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