水中铬含量测定实验的改进

Improvement in the experiment of determination of chromium in water

水中铬含量测定实验对实验者操作技能要求很高。物理专业学生没有接受过基础化学实验训练,难以规范地使用多种化学分析仪器,准确地检测出溶液中铬离子浓度比较困难,学习效果不理想。对传统的教学方案进行了调整,适当地降低了实验的操作难度,用移液枪替代微量滴定管,增加平行实验次数,并且用计算机辅助分析实验数据。改进的实验方法帮助学生更好地理解实验的要点,加深对化学知识的理解,提高了实验的训练效果。

The experiment of “determination of chromium in water” requires high operation skills for experimenters. The physics major students do not receive basic chemistry experiment trainings and the standard use of a variety of chemical analysis instruments. 1 t is difficult for them to measure the chromi-um ion concentration in solution,and so the study is not effective. We adjusted the traditional teaching scheme,including the reduction the difficulty of the experiment,replacing a pipette with a microburet, increasing the number of parallel experiments and using computer software Origin to analyze the experi-mental data. The improved experimental methods help students better understand the main points of the experiment,deepen their understanding of chemistry and improved the training effect of experiments.