氟的测定方法主要有茜素铜比色法、硝酸钍容量法及氟离子选择电极法[1]。前两种方法虽然准确度高,但消耗试剂多,费时,且硝酸钍有放射污染而很少使用。离子选择电极法具有操作简便、响应速度快等特点,适用批量样品测定。1实验部分1.1主要仪器与试剂 Determination of fluoride are mainly alizarin copper colorimetric method, thorium nitrate volumetric method and fluoride ion selective electrode method [1]. Although the first two methods have high accuracy, they consume more reagents and are time consuming, and thorium nitrate is rarely used due to radioactive contamination. Ion selective electrode method has the advantages of simple operation, fast response, suitable for batch sample determination. 1 Experimental 1.1 The main instruments and reagents