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    某化学兴趣小组同学用Na2CO3溶液和浓HCl来研究简易灭火器的反应原理时，对废液的成分进行探究。

    【推理假设】  废液的成分中一定有               ，可能有Na2CO3或盐酸．

    【实验探究】  确定废液成分中是否含有Na2CO3或盐酸

         请你协助兴趣小组的同学完成实验探究，并完成实验报告。

    实验步骤

    现象

    结论

    该废液中一定没有盐酸                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      

    该废液中一定含有Na2CO3


                NaCl          

    实验步骤

    现象

    结论

    取样于试管中，滴加石蕊试液，振荡，观察现象

    溶液不变红色

    该废液中一定没有盐酸                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      

    另取样于试管中，滴加稀盐酸，观察现象

    有气泡产生

    该废液中一定含有Na2CO3

    （答案合理即可）


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