发现问题在当天的化学课上,老师向同学们介绍了拉瓦锡研究空气成分的实验,并演示了空气中氧气含量测定的实验。放学了,张雷、刘雯和陈帅仍然在讨论着老师在做演示实验时出现的问题。原来,老师在把点燃的红磷放入装置(见图1)中时,由于没有及时盖好橡皮塞,结果使得测定空气中氧气体积含量大于1/5了。 Found the problem In the day's chemistry class, the teacher introduced to the students Laval's experimental study of air composition, and demonstrated the determination of oxygen in the air experiments. After school, Zhang Lei, Liu Wen and Chen Shuai are still discussing the problems that teachers face when doing demonstration experiments. It turned out that the teacher put the ignited red phosphorus into the device (see Figure 1), the lack of rubber covered in time as a result of the test results in the determination of oxygen in the air volume content of more than 1/5 of the.