题干

向一定质量、一定溶质质量分数的稀盐酸中逐滴加入某碳酸钠溶液.实验过程中,产生气体质量与加入碳酸钠溶液的质量关系如图所示,试计算:


①恰好完全反应时,生成气体的质量为多少克?

②恰好完全反应时,所加碳酸钠溶液中Na2CO3的质量是多少?

③若恰好完全反应时所得溶液的溶质质量分数为5%,则稀盐酸的溶质质量分数是多少?

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答案(点此获取答案解析)

解:①恰好完全反应时生成CO2的质量为4.4g;

②设恰好完全反应时,所加碳酸钠溶液中Na2CO3的质量为x,碳酸钠完全反应生成氯化钠的质量为y,消耗稀盐酸的溶质质量为z

Na2CO3+2HCl═2NaCl+H2O+CO2

106 73117 44

x z y 4.

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完形填空

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