九年义务教育三年制初级中学教科书——《化学》（全一册）第８４页中，有一“木炭还原氧化铜”［实验５－４］。很多人认为这个实验现象不明显，实验成功率很低，所以在很多的教学参考资料上，常常有改进这个实验的方法。有的实验前把炭粉和氧化铜用水调成糊状，抹在试管中烘 Nine-year compulsory education Three-year primary school textbooks - “Chemistry” (a full volume) page 84, there is a “copper reduction of copper oxide” [Experiment 5-4]. Many people think that this experimental phenomenon is not obvious, and the success rate of experiments is very low. Therefore, in many teaching reference materials, there are often ways to improve this experiment. In some experiments, the carbon powder and copper oxide were transferred into a paste by water and wiped in a test tube.