有趣的实验
<p>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。</p><p><span word="Today">Today</span>, <span word="Mr">Mr</span>. <span word="Yang">Yang</span> <span word="walked">walked</span> <span word="into">into</span> <span word="the">the</span> <span word="classroom">classroom</span> <span word="with">with</span> <span word="a">a</span> <span word="smile">smile</span> <span word="on">on</span> <span word="his">his</span> <span word="face">face</span> <span word="and">and</span> <span word="said">said</span> <span word="to">to</span> <span word="everyone">everyone</span>, "<span word="it">it</span>'<span word="s">s</span> <span word="a">a</span> <span word="lucky">lucky</span> <span word="day">day</span> - <span word="I">I</span> <span word="picked">picked</span> <span word="up">up</span> <span word="a">a</span> <span word="burning">burning</span> <span word="handkerchief">handkerchief</span> <span word="in">in</span> <span word="the">the</span> <span word="morning">morning</span>!" <span word="After">After</span> <span word="hearing">hearing</span> <span word="this">this</span>, <span word="there">there</span> <span word="was">was</span> <span word="a">a</span> <span word="commotion">commotion</span> <span word="in">in</span> <span word="the">the</span> <span word="classroom">classroom</span> <span word="and">and</span> <span word="everyone">everyone</span> <span word="was">was</span> <span word="talking">talking</span> <span word="about">about</span> <span word="it">it</span>. <span word="Some">Some</span> <span word="said">said</span>, "<span word="Miss">Miss</span> <span word="Yang">Yang</span> <span word="must">must</span> <span word="be">be</span> <span word="cheating">cheating</span>!" <span word="Some">Some</span> <span word="said">said</span>, "<span word="yes">yes</span>! <span word="Yes">Yes</span>! <span word="There">There</span> <span word="is">is</span> <span word="indeed">indeed</span> <span word="a">a</span> <span word="burning">burning</span> <span word="handkerchief">handkerchief</span>! " <span word="At">At</span> <span word="this">this</span> <span word="time">time</span>, <span word="Mr">Mr</span>. <span word="Yang">Yang</span> <span word="said">said</span>, "<span word="if">if</span> <span word="you">you</span> <span word="don">don</span>'<span word="t">t</span> <span word="believe">believe</span> <span word="in">in</span> <span word="doing">doing</span> <span word="an">an</span> <span word="experiment">experiment</span>, <span word="how">how</span> <span word="about">about</span> <span word="it">it</span>?" "<span word="Good">Good</span>! <span word="Good">Good</span>! " <span word="The">The</span> <span word="students">students</span> <span word="said">said</span> <span word="in">in</span> <span word="unison">unison</span>.</p><p>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。</p>
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