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人教版义务教育课程标准实验教科书化学九年级上册中的[实验6-5]如图1所示,将收集有二氧化碳的集气瓶沿烧杯边沿慢慢往烧杯中倾倒,下面的蜡烛先熄灭,上面的蜡烛后熄灭。这说明二氧化碳密度比空气大,二氧化碳不支持燃烧,也不能燃烧。但在具体实验中,往往由于操作难以把握而造成上层蜡烛先熄灭,导致实验失败。贵刊2010年第3期第25页刊登了肖利辉对该实验的改进一文,改进装置如图2所示。笔者对该实验的改进方法则有所不同。
People's Education Edition Compulsory Education Curriculum Standard Experimental Textbook Class IX of Chemistry [Experiment 6-5] As shown in Figure 1, the collection of carbon dioxide collection bottle along the edge of the beaker slowly poured into the beaker, the candle below the first extinguished , The candle above goes out. This shows that the density of carbon dioxide than the air, carbon dioxide does not support the combustion, it can not burn. However, in specific experiments, it is often unsuccessful because the operation is difficult to grasp and the upper candle is extinguished first. The third issue of 2010 No. 25 page published Xiao Lihui improvement of the experiment a text, the improvement device shown in Figure 2. The author of the experiment to improve the method is different.