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今天，杨老师面带微笑地走进教室，对大家说：“今天运气真好—一大早就捡到了一块烧不破的手帕！”听了这话，教室里一阵骚动，大家都议论纷纷。有的说：“杨老师肯定在骗人！”有的说：“对！对！的确有烧不破的手帕！”这时，杨老师说：“不信做个实验，怎么样？”“好！好！”同学们异口同声地说。 Today, Mr. Yang walked into the classroom with a smile on his face and said to everyone, "it's a lucky day - I picked up a burning handkerchief in the morning!" After hearing this, there was a commotion in the classroom and everyone was talking about it. Some said, "Miss Yang must be cheating!" Some said, "yes! Yes! There is indeed a burning handkerchief! " At this time, Mr. Yang said, "if you don't believe in doing an experiment, how about it?" "Good! Good! " The students said in unison. 于是，杨老师开始做实验了。她先拿出一块上面绘有一只可爱的小白兔图案的手帕，把它放入了含有70%酒精和３0%水的混合液体里。等全部被浸湿后，老师再把手帕拿出来，放入另一个事先准备好的盆里，又点燃一根火柴，那火柴上的火苗一碰手帕，整块手帕就立刻被烈火围住，只见火苗越窜越高，火舌足有一尺来高呢！这时，我看到手帕上的“小白兔”在熊熊烈火中“拼命挣扎”，我越看越心疼，真希望火快点熄灭。突然一股浓浓的酒精味扑鼻而来——原来是杨老师把火扑灭了。接着杨老师再把手帕展示我们看，“啊！完好无损！”有人惊奇地喊道，“呀！太神奇了！”我情不自禁地想。正在我们惊奇又纳闷的时候，杨老师给出了答案，原来：酒精是易燃的，而水是吸收热量的，在燃烧的过程，水一面吸收热量一面将火与手帕隔开，这样，手帕就不会被烧破了。 | 
