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问题:

(8分)有三种白色粉末,分别是碳酸钠、碳酸钙和氯化钠中的一种。请设计一个实验方案,把这三种粉末

(8分)有三种白色粉末,分别是碳酸钠、碳酸钙和氯化钠中的一种。请设计一个实验方案,把这三种粉末区分开来。叙述实验操作、预期现象和结论。

实验操作

预期现象与结论


  参考答案

正确答案:

实验操作

预期现象与结论

分别取少量三种粉末于洁净的试管中,加入足量的水充分溶解。

有一支试管中的粉末不溶解,该粉末是碳酸钙。

向得到澄清溶液的两支试管中分别滴入适量的稀盐酸

有气泡产生,溶解前的粉末是碳酸钠;无明显现象的,溶解前的粉末是氯化钠。

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