铜与浓硝酸反应演示实验的改进山东日照师范学校刘成玲在现行的中师化学教科书中，讲到浓硝酸与铜片反应的演示实验时，是将盛有铜片与浓硝酸的试管用无色透明的塑料袋罩住，然后观察生成的红棕色二氧化氮的颜色。此操作方法存在以下两个问题：１．用塑料袋盛装气体，生成... Improvements in Demonstration Experiments of Copper and Concentrated Nitric Acid Reactions Liu Chengling of Rizhao Teachers’ College of Shandong Province, in the current textbook on normal chemistry, said that when conducting a demonstration experiment of the reaction of concentrated nitric acid and copper, the test tube containing copper and concentrated nitric acid was colorless. Cover it with a transparent plastic bag and observe the color of the red-brown nitrogen dioxide produced. This operation method has the following two problems: 1. Gas filled with plastic bags, generate...