紫外分光光度法测定丁香酚的电离常数

Determination of the ionization constant of eugenol by the spectrophotometric method

目的测定丁香酚电离常数 (pKa)。方法在 (2 5± 0 5 )℃条件下 ,选择 2 94nm为分析波长 ,采用紫外分光光度法进行测定。结果测得丁香酚的电离常数pKa 为 1 0 2 1± 0 2 ,RSD为 0 2 %。结论该方法简便、快速 ,重现性好 ,适用于难溶性一元弱酸 (碱 )

Objective To determine the ionization constant of eugenol.Method At room temperature, 294 nm was selected as the analytical wave length.The spectrophotometric method was used.Results The pK a was 10.21±0.2,and RSD 0.2%.Conclusions The procedure is simple, rapid and reliable,and can be applied for the determination of the ionization constant of monoacid or monoacidic base.