Abstract This paper improved the experiment for the main factors that affect salt hydrolysis balance in the textbook. Experiments confirmed the acid solution with litmus changed colour at pH=5.0 and room temperature. According to the ionization equilibrium constants of water and ammonia, 0.09 mol·L-1 ammonium sulfate solution was quantitatively calculated and prepared. The initial colour of ammonium sulfate solution was purple after the addition of litmus. By comparing the colour changes during heating and cooling, the equilibrium movement process for the hydrolysis of ammonium ion was visualized. By adding strong base weak acid salt into “coloured solution”, the essence of double hydrolysis reaction was explored, and the influence of temperature and concentration on salt hydrolysis was further verified. The improved experiment was simple, quick, and effective, and the visualization of the experiments helped students to construct a complete cognitive model.
YANG Jie, JIANG Jian-Wen, ZENG Cheng-Hui. Experiment Design of Salt Hydrolysis Teaching Based on Visualization of Thinking[J]. Chinese Journal of Chemical Education, 2023, 44(3): 104-110.
