题目

下述实验设计能够达到目的的是( )编号实验目的实验设计A除去CO2中少量的SO2将混合气体通过饱和Na2CO3溶液B除去Cu粉中混有的CuO向混合物中滴加适量稀硝酸C检验溶液中是否含有Fe2+向溶液中滴入氯水后,再滴加KSCN溶液D证明H2CO3酸性比H2SiO3强将CO2通入Na2SiO3溶液中   答案：D 【解析】CO2和SO2都与Na2CO3溶液反应,应选择饱和NaHCO3溶液,A项错误;Cu粉与稀硝酸反应,B项错误;检验Fe2+,应先滴加KSCN 溶液,不显红色,再滴入氯水,C项错误;将CO2通入Na2SiO3溶液中得到H2SiO3白色沉淀即可证明H2CO3酸性比H2SiO3强,D项正确。  根据句意和汉语注释，写出单词的正确形式。1.Parents should have more ______________ (交流) with their children.2.Finally, the climber ______________ (设法完成) to get to the top of the mountain.3.The rich man has a lot of poor ______________ (亲戚). He gives them much money every year.4.It is amazing that a cow has four ______________ (胃).