试题与答案

由分子构成的物质,发生化学变化的实质是( ) A.分子间的空隙发生变化 B.物质

题型:选择题

题目:

由分子构成的物质,发生化学变化的实质是(  )

A.分子间的空隙发生变化

B.物质状态发生改变

C.物质颜色变了

D.分子本身起了变化,变成其它分子

答案:

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