题干

下列说法正确的是(      )

A:等质量的乙烯和丙烯中,所含碳原子数之比为2∶3

B:等体积、等浓度的NH4Cl溶液和稀氨水中,所含NH4+的数目相等

C:等物质的量的Cl2分别与足量的Fe和Cu反应,转移的电子数相等

D:等物质的量的过氧化钡(BaO2)和Ba(OH)2固体中,阴阳离子个数比均为2∶1

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答案(点此获取答案解析)

C

同类题5

    One terribly cold day, a snowstorm hit our area. Needing firewood, I quickly set out with my best friend, Bruce, to look for a tree to cut down. Cutting down a tree in a snowstorm can be dangerous. ① So to have a friend who could warn me of dangerso was important.
    When I chose a big 23-meter-tall tree and prepared to cut it down, Bruce suddenly warned me, “Don't cut down that tree! It's too close to the power line!” I wasn't sure about it. So I decided to disregard his warning. I couldn't wait to finish the job and go back home. I began cutting down the tree.② When the tree fell, there was no longer any doubt whether my friend was right.
    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.
    ③Within two hours, the workers removed the tree. Soon the snowstorm calmed down——but not my mother. Even though she was glad that I wasn't hurt, my mother was still serious with me. After all(毕竟), I shouldn't have brushed off my friend's warning.