题干

为了证明(NH4)2Fe(SO4)2·6H2O(硫酸亚铁铵晶体)的成分中含有NH、Fe2、SO和H2O,下列实验叙述中不正确的是

A:取少量硫酸亚铁铵晶体放入试管,加热,试管口有液体生成,则可证明晶体的成分中含有结晶水

B:硫酸亚铁铵晶体溶于水,得淡绿色溶液,滴入2滴KSCN溶液,溶液不显红色,再滴入几滴新制氯水,溶液变为红色,则可证明晶体的成分中含有Fe2

C:硫酸亚铁铵晶体溶于水,加少量稀盐酸,无现象,再滴入几滴BaCl2溶液,有白色沉淀生成,则可证明晶体的成分中含有SO

D:取少量硫酸亚铁铵晶体放入试管,加浓NaOH溶液,加热,试管口湿润的蓝色石蕊试纸变红,则可证明晶体的成分中含有NH

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答案(点此获取答案解析)

D

同类题5

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    The tree caught the power line, bringing it to the ground. I considered cutting the tree off the line. After all, electricity can't travel through wood. As I reached out my finger to touch the tree, pain ran up my arm and through my head. I had been shocked!
    After I returned home and told my mother what happened, she quickly called the power company. Workers from the power company soon arrived. One of them asked if I had touched the tree, and when I told him I had, his face turned pale. “You should have been killed,” he said. It was my boots that saved my life.
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