Spectrophotometric Determination of the Thermodynamic pK Value of Picric Acid in Water at 25 °C
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چکیده
The thermodynamic p K value of picric acid was determined spectrophotometrically in water containing hydrochloric acid to repress the ionization. The pK value 0.33 ( i£«0 .46) was obtained from da ta a t 450 m/*. At tempts to determine the p K value by potent iometr ic t i t rat ions of picric acid and by spectrophotometric measurements of picric acid solutions in the near-saturat ion range did not yield satisfactory results. The new pK value is compared With previously published values.
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تاریخ انتشار 2006