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有毒气体的实验应在通风橱内进行。目前中学里建有通风橱的学校是很少的。而课堂演示实验又不便在通风橱内进行。中学化学课本中有关氯气的一些实验,都是在讲台上沿用老方法——用燃烧匙盛药放入集气瓶中进行反应。这些反应剧烈且放热,实验时必然会有大量有毒气体逸散到空气中,造成空气污染;用的药量大,现象又不十分明显,针对上述情况,我们对教材上的演示实验作了改进,设计了氯气的系列实验。实践证明,改进后的演示实验有下列优点:1.现象明显,所需时间短,一般每个实验不超过3分钟;2.用药量少,操作简便;3.有毒尾气可以吸收,空气无污染或极少污染,4.氯气的实验室制法和性质的一系列实验可以一气呵成;5.
Toxic gas experiments should be carried out in a fume hood. Currently there are very few schools in secondary schools with fume hoods. The classroom demonstration experiment inconvenient in the fume hood. Some experiments on chlorine in chemistry textbooks in middle schools are based on the old method of using psoriasis medicine in a gas collection bottle to react. These reactions are intense and exothermic, the experiment will inevitably have a large number of toxic gases escaping into the air, causing air pollution; with a large dose, the phenomenon is not very clear, in view of the above, we demonstrated on the textbook experiments Improve, design a series of experiments chlorine. Practice has proved that the improved demonstration experiment has the following advantages: 1. The phenomenon is obvious, the time required is short, usually less than 3 minutes per experiment; 2. Less medication, easy to operate; 3. Toxic exhaust can absorb air pollution Or minimal pollution, 4. A series of laboratory tests of chlorine gas and properties of a series of experiments can be done in one go;