JIA Li, LAI Tian-Cheng, MA Kai-Guo, MA Yan-Zi, ZHAO Hao, LI Wei-Hong**
National Demonstration Center for Experimental Chemistry Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
Abstract In general chemistry lab, a simple photometer was constructed by using monochromatic light-emitting diode (LED), Lego bricks and other electronic components. Two ways of construction were illustrated, featuring the simple structure, visualized light path and low cost. The concentration of Fe(Ⅲ) was measured by the student-made photometer, and the experimental data were compared with that given by a commercial photometer. Within a certain range of concentration, there is a good linear correlation between the absorbance and the concentrations of standard ferric solutions, which well meets the requirements of the basic laboratory teaching. These results reveal that such a simple student-made photometer can be used as an alternative to the commercial photometer in laboratory teaching. Two years of teaching practice and improvement demonstrate that using the student-made photometer in teaching of quantitative determination of Fe(Ⅲ) can inspire the students' interests and enthusiasm of learning, enhance the hands-on abilities, independent thinking and problem-solving, thus improve teaching effects.
JIA Li, LAI Tian-Cheng, MA Kai-Guo, MA Yan-Zi, ZHAO Hao, LI Wei-Hong. Determination of Fe(Ⅲ) Using LED and LEGO Bricks[J]. Chinese Journal of Chemical Education, 2021, 42(20): 74-78.