问题 实验题

小强和几位同学在实验室用下列装置制取几种气体:

(1)小强用高锰酸钾制取氧气,他选择上述装置中的A作为制取装置。你认为A装置中还缺少___________。写出该反应的化学方程式_____________________________________。

(2)如果采用排水法收集氧气,应该与___________装置连接,当收集氧气实验结束后,应该如何操作 ?________________________________________________________________。

答案

(1)一团棉花; 2KMnO4K2MnO4 + MnO2 + O2

(2)D; 先取下导管,后熄灭酒精灯

多项选择题
阅读理解

阅读理解.

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