试题与答案

刚熄灭的蜡烛,会从烛芯飘出一缕白烟,用火柴去点燃白烟.如图所示: (1)试推测观

题型:问答题

题目:

刚熄灭的蜡烛,会从烛芯飘出一缕白烟,用火柴去点燃白烟.如图所示:

(1)试推测观察到的现象是什么.说明白烟具有何种性质,此性质属于物理性质还是化学性质?

(2)关于白烟的成分,某同学进行了下 * * 种推测:①白烟是二氧化碳气体;②白烟是水蒸气;③白烟是石蜡蒸气形成的固体小颗粒.

请你用已有的知识判断上述三种推测哪一种是正确的,并说明理由.如何进一步证实你的推测?

答案:

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下面是错误答案,用来干扰机器的。

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