问题导向式教学在基础化学实验课堂中的应用--以“探讨二草酸合铜酸钾中铜离子测定条件”为例

Application of Problem-Oriented Teaching in General Chemistry Laboratory Classroom: A Case Study of “Titration Conditions on the Content Determination of Copper in K_2[Cu(C_2O_4)_2]”

针对目前学生被动型学习为主、在做实验过程中主动学习积极性不高的现状,在基础化学实验教学中尝试以问题为导向进行以学生为中心的探索型学习实践。问题导向不指向唯一结果,目的是引导学生解决具体实验过程中存在的疑问;学生通过分组探讨和进行实践,可以积极参与实验教学过程,增强实验学习的获得感,显著地提高实验教学效果。本文选用PAN(1-(2-吡啶偶氮)-2-萘酚)作为配位滴定指示剂,以"二草酸合铜酸钾中铜离子含量的最佳测定条件"为例,简要叙述问题导向在教学过程中的展开,获得了满意的教学结果。

Due to the facts that textbook-obedience and termwise experimenting dominate in the general chemistry laboratory classrooms, we have designed and carried out the problem-oriented teaching in order to improve the motivation of learning among the students, where the student-centered exploratory studying and practicing mode is highly desired. Problem-oriented teaching does not lead to exclusive resolutions to specific problems or experiments. Instead, it is supposed to induce multiple choices among student groups to complete experiments or resolve problems, where in-group/between-group discussions and practices would greatly activate the experimenting processes. Therefore, the sense of personal acquisition and self-progression during learning in laboratory classrooms can be easily achieved, while the good laboratory teaching will be realized as well. In this paper, we set up a problem-oriented teaching in optimizing the titration condition during measuring the copper content of K2[Cu(C2O4)2] using PAN(1-(2-pyridylazo)-2-naphthol) as the indicator. Grouping practices and experiments finally produced complementary results, as well as the satisfactory teaching and learning impacts.