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现行初中化学课本,是在初中化学试用本的基础上改编而成的。在改编时,除在内容上进行了适当的调整外,在演示实验方面,也作了进一步的改进。但个别演示实验,还有欠妥之处。 如[实验2—6],用铁罐头筒做氢气和空气混和点燃爆炸的演示实验,就不够安全。因为爆炸实验的结果,能把铁罐头筒抛上天花板并反弹下来,铁罐头筒既硬又重,如果落在演示实验的讲台上,就有损坏实验用品的危险,如果落在座位上,可能伤害学生。因此,这是不符合安全性原则的。
The current junior high school chemistry textbook is based on the junior high school chemistry trial book. At the time of adaptation, in addition to proper adjustments in content, further improvements have been made in demonstrating experiments. However, there are still defects in individual demonstration experiments. For example, [Experiment 2-6], it is not safe to use a canned iron cylinder as a demonstration experiment for hydrogen and air mixing to ignite the explosion. As a result of the explosion experiment, the canister can be thrown onto the ceiling and bounced off. The tin can is hard and heavy. If it falls on the podium of the demonstration experiment, there is a danger of damaging the experimental supplies. If it falls on the seat, it may be Injury students. Therefore, this is not consistent with the principle of security.