题干

根据下列装置图回答问题(装置图用符号表示)
(1)写出编号①②的仪器名称:①____②____
(2)双氧水(H2O2)是无色液体,可发生如下化学反应:2H2O2=MnO22H2O+O2↑,在实验室利用此反应制取氧气时,应选用的气体发生装置是:____ .
(3)实验室用大理石和盐酸反应制取二氧化碳,在生成的气体中混有少量氯化氢和水蒸气.C装置可用于除掉水蒸气,可选用____ 作干燥剂(填名称).根据下列各备选试剂的性质,利用D装置除掉氯化氢时,应选择的最佳试剂是:____ (填序号)①饱和石灰水  ②氢氧化钠溶液  ③碳酸钠溶液  ④饱和碳酸氢钠溶液
2NaOH+CO2═Na2CO3+H2O Na2CO3+H2O+CO2═2NaHCO3
Na2CO3+2HCl═2NaCl+H2O+CO2↑   NaHCO3+HCl═NaCl+H2O+CO2↑
(4)将制取二氧化碳的装置按发生、净化和收集的顺序进行连接,装置依次为____  (填装置序号)
上一题 下一题 0.0难度 选择题 更新时间:2017-06-12 12:23:19

答案(点此获取答案解析)

试管,酒精灯,B,浓硫酸,④,d→c→a→b→e→f

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