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初三化学课本第三章第四节介绍,二氧化碳是一种比空气重、没有颜色的气体。可以象倾倒液体那样,把二氧化碳从一个容器倒到另一个容器里。在一般情况下,二氧化碳既不燃烧,也不能支持燃烧。二氧化碳的这些性质,集中通过课本P112介绍的“二氧化碳熄灭蜡烛火焰”的一个演示实验来验证。但按课本图示操作,实验很难得到预期的效果。经常是上面一支蜡烛先熄灭,而不是下面一支蜡烛先熄灭,如下图1:
The third day of chemistry textbook Chapter IV, Section IV describes, carbon dioxide is a heavier than air, no color of gas. You can pour carbon dioxide from one container into another just as it does to pour liquid. In general, carbon dioxide neither burns nor supports combustion. These properties of carbon dioxide are validated through a demonstration experiment with the “Carbon Dioxide Extinguished Candle Flame” presented in P112. However, according to the textbook operation, the experiment is difficult to get the desired results. Often the candle above is extinguished first rather than the candle below to extinguish first, as shown in Figure 1 below: