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我们在做《氨的制取与性质》一实验中,大试管炸裂很多。据实验老师统计,我们6个班每班12个组做该实验共用27根大试管,炸裂14根,50％还多! 针对这个问题,我作了如下推测: ①试管预热时间短,局部受热温度过高,实验中试管炸裂; ②药品堆积在试管底,未均匀铺开,受热不均匀,实验中破裂; ③实验完毕,在将试管下取过程中,试管翻转或管口高于管底,管口的水倒流至试管底,试
In the experiment of “Preparation and Properties of Ammonia”, the large test tube burst a lot. According to the statistics of the experimental teacher, 12 groups of 6 classes in our class used the experiment to share 27 large test tubes and burst 14 pieces, more than 50%! In response to this problem, I made the following assumptions: 1 The tube warm-up time is short, local The heat temperature is too high, the test tube ruptures; 2 The medicines accumulate at the bottom of the test tube, do not spread evenly, and the heat is not even, and it breaks during the experiment; 3 After the experiment is finished, during the process of taking the test tube down, the test tube is overturned or the nozzle is higher than the tube At the bottom, the water in the nozzle back to the bottom of the test tube.