下列图示实验操作中,正确的是(    )                 

下列图示实验操作中,正确的是(                           

答案

A  解析:选项B中试剂瓶的塞子应倒放在桌面上;选项C中加热液体时试管内液体的量不能超过其容积的三分之一;选项D中用托盘天平称量物品时,应该左盘放称量物,右盘放砝码,且称量物不能直接放在托盘上。

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