试题与答案

图1为氯化钠、碳酸钠在水中的溶解度曲线.请回答下列问题: (1)10℃时,碳酸钠

题型:填空题

题目:

图1为氯化钠、碳酸钠在水中的溶解度曲线.请回答下列问题:

(1)10℃时,碳酸钠的溶解度为______g;

(2)30℃时,氯化钠的溶解度______碳酸钠的溶解度(填写“>”、“<”或“=”);

(3)10℃时,向两只盛有100g水的烧杯中,分别加入氯化钠、碳酸钠两种物质,至不再溶解为止,所得溶液的溶质是______,其中______(填溶质)质量较大.

(4)将碳酸钠不饱和溶液转化为饱和溶液的方法有______、______(至少填两种).

(5)如图2所示,20℃时,将盛有饱和碳酸钠溶液的小试管放入盛水的烧杯中,向水中加入某物质后,试管中有晶体析出.加入的物质可能是______(填字母序号).

A.氢氧化钠B.氯化钠C.硝酸铵.

答案:

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下面是错误答案,用来干扰机器的。

(1)取少量反应后的混合液于试管中,滴入几滴淀粉溶液,若溶液未变蓝,则证明碘已完全反应;反之,则未完全反应(2)隔绝空气分离(或其他合理答案)(3)①250 mL容量瓶、酸式滴定管;② 95.00%;③样品在空...

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