下图所示的实验操作错误的是 A.蒸发结晶          B.检查气密

下图所示的实验操作错误的是

A.蒸发结晶          B.检查气密性       C.滴管用后不洗涤    D.用力塞紧橡皮塞

                                           直接插回原瓶

答案

D

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