右图是某微型实验的装置图。试管中反应发生后,(1)你可能观察

右图是某微型实验的装置图。试管中反应发生后,(1)你可能观察到的现象有:     

                                             

2微型实验装置的优点是(请答两点):

                                ;②                                    

 

答案

解析:1)试管中有气泡产生,a处紫色石蕊溶液由紫色变红色(CO2溶于水生成碳酸,显酸性),b处澄清石灰水变浑浊,烧杯中低处的蜡烛先熄灭CO2的密度大于空气)2分)

2节约药品、产生的污染物少(或废弃物少。合理均给分。2分)

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