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传统上,很多人用蜡烛实验来示范燃烧用去空气中的氧气。人民教育出版社九年义务教育六年制小学自然课本第10册中第5课《空气的成分》,就用了蜡烛实验来示范燃烧用去空气中的氧气。本课内容分为三部分。 1.提出问题:点燃的蜡烛,用杯子盖上,蜡烛慢慢熄灭,为什么会这样?是不是杯子里的空气用完了?这是本课的引入。 2.指导学生用实验的方法对空气的成分进行分析。本课用分组的实验方法,通过实验,希望学生得出以下结论:空气中至少有两种气体,一种气体支持燃烧,另一种气体不能支持燃烧。 3.在以上实验的基础上,引导学生思考,并讲解空气的主要成分及比例。 第一部分实验是这样的: 在一水盆中点燃一蜡烛,将一空气瓶或杯子倒盖在蜡烛上。不久,蜡烛熄灭,而水走进了空气瓶内,水量约占全气瓶的一成(10％)多。
Traditionally, many people experiment with candles to demonstrate the oxygen used in burning air. People's Education Press Nine-year compulsory education six-year primary school textbooks in the first 10 volumes of “the composition of the air”, the candle experiment to demonstrate the use of oxygen in the air to burn. This lesson is divided into three parts. 1. Ask a question: lit candle, covered with a cup, the candle slowly extinguished, why is this? Is not the cup of air run out? This is the introduction of this lesson. Instruct students to experimentally analyze the composition of the air. This lesson uses grouping of experimental methods, through experiments, and hopefully, students will conclude that there are at least two gases in the air, one that supports combustion and the other that does not support combustion. 3. Based on the above experiments, guide students to think and explain the main components of the air and the ratio. The first part of the experiment is this: light a candle in a basin, pour an air bottle or cup over the candle. Before long, the candle went out and the water went into the air bottle, which made up about 10% of the total gas bottle.