在配位滴定法中,测定水的硬度是学生必做实验。由于我校水的硬度很软,在测定硬度时的标准溶液消耗量只有3～4mL,致使体积误差大大超过容量分析的要求。为解决水样问题,曾尝试用增加Cg~(2+)、Mg~(2+)量增加水的硬度的办法,这样,不仅消耗大量药品,增加了实验室的工作量,更重要的是,学生还会感到所测水是“假水”,降低了实验意义的兴趣。 In the coordination titration method, the determination of water hardness is the student must do experiments. Due to the hardness of our school water is very soft, the standard solution consumption in the determination of hardness is only 3 ~ 4mL, resulting in the volume error greatly exceeds the capacity analysis requirements. In order to solve the water sample problem, attempts have been made to increase the hardness of water by increasing the amount of Cg2 + and Mg2 + so as to not only consume a large amount of drugs but also increase the laboratory workload and, more importantly, , Students will feel the measured water is “fake water”, reducing the interest of the experimental significance.