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物质组成的综合计算

> 以下说法正确的是 A.高锰酸钾加热后产生氧气，说明高锰酸钾中含有氧气 B.过氧化氢溶液不加二氧化锰会产生氧气，会使试管口带火星的木条复燃 C.用排水法收集的氧气不纯是因为装置漏气了 D.用红磷测定空气中氧气的体积分数时，一定要待集气瓶中的气体冷却后才能打开弹簧夹

问题：

发布时间：2024-12-17

以下说法正确的是

A.高锰酸钾加热后产生氧气，说明高锰酸钾中含有氧气
B.过氧化氢溶液不加二氧化锰会产生氧气，会使试管口带火星的木条复燃
C.用排水法收集的氧气不纯是因为装置漏气了
D.用红磷测定空气中氧气的体积分数时，一定要待集气瓶中的气体冷却后才能打开弹簧夹

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