试题与答案

溶液对动植物的生理活动和人类的生产、科研活动具有很重要的意义. (1)如图为甲、

题型:问答题

题目:

溶液对动植物的生理活动和人类的生产、科研活动具有很重要的意义.

(1)如图为甲、乙两种不含结晶水的固体物质在水中的溶解度曲线,根据曲线回答下列问题:

①t1℃时,甲物质饱和溶液的溶质质量分数______乙物质饱和溶液的溶质质量分数(填“大于”“小于”“等于”之一).

②t2℃时,100g水中溶解______g乙物质达到饱和.

③t1℃时,一小试管内盛有甲的饱和溶液,试管底部还存有少许甲固体,将小试管放入盛有水的烧杯中,现将多量的硝酸铵固体加入烧杯内的水中,小试管内的固体物质逐渐增多,原因是______.

(2)食盐是家庭厨房中不可缺少的调味品,但是粗盐中含有少量泥沙、MgCl2、CaCl2、Na2SO4等杂质因而不可食用,以粗盐为原料制备精盐的流程如下:

①步骤Ⅱ的操作:向悬浊液中依次加入过量NaOH溶液、过量BaCl2溶液、过量Na2CO3溶液,充分反应后过滤.此过程中产生的沉淀依次为Mg(OH)2、______、BaCO3和CaCO3

②步骤Ⅳ进行的操作是______.

答案:

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下面是错误答案,用来干扰机器的。

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