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酸和碱的中和作用在分析化学上的应用已有悠久的历史。利用容量法測定酸、碱工业制品,广泛地应用于工业分析及药品分析,不过这些都限于强酸和强碱,在水中有高度离解作用。通常在水溶液中进行滴定,中和的等当点很容易用适当的指示剂观察出来,或由电位滴定、电导滴定測定电势、导电度的突跃变化。但还有一些在水中仅有微弱离解作用的弱酸和弱碱,例如有机物羧酸、酚、磺酰胺(-SO_2NH-)和胺、亞胺、氨基酸等一类化合物,就不能在
The neutralization of acids and bases has a long history in analytical chemistry. The use of volumetric method for the determination of acid and alkali industrial products, widely used in industrial analysis and pharmaceutical analysis, but these are limited to strong acid and alkali, highly dissociating in water. The titration is usually carried out in aqueous solution. The neutralization point is easily observed with a suitable indicator or potentiometric and conductometric titration. However, there are some weak acids and weak bases, such as organic carboxylic acids, phenols, sulfonamides (-SO_2NH-) and compounds such as amines, imines and amino acids that only weakly dissociate in water.