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【题目】化学来源于生活,圆梦中学的化学兴趣小组做了以下趣味实验:一定温度下,

有一杯食盐水,杯底尚有大量食盐固体不能溶解,现将新鲜的萝卜块放入其中,放置一段时

间。小组同学分别得出了以下说法,其中说法错误的是

A.原食盐水一定是饱和溶故 B.萝卜块质量一定减少

C.杯中的食盐固体一定全部溶解 D.溶液的质量一定增加

【答案】C

【解析】

溶液的初始现象是有少量食盐固体没有溶解,说明溶液已经是饱和状态,A选项正

确;将新鲜的萝卜放入食盐水中,我们能看到萝卜会萎缩的现象,因为萝卜体内的

水分会进入食盐溶液中,因此萝卜块质量减少而溶液的质量增加,选项BD正确。

因为进入溶液的水量很小,能不能将未溶解的氯化钠全部溶解不一定,所以C选项

错误。

知识点:溶液状态及常识。

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