题干

设NA为阿伏加德罗常数的值,下列与NA有关的说法正确的是(   )

A:在反应KClO3+6HCl=KCl+3Cl2↑+3H2O中,当得到标准状况下67.2 L Cl2时,反应中转移的电子数为6 NA

B:6.0 g SiO2晶体中含有的硅氧键数目为0.2 NA

C:标准状况下,22.4 L NO和11.2 L O2混合后气体的分子总数为NA

D:S2和S8的混合物共6.4 g,其中所含硫原子数一定为0.2 NA

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D

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Finally Home

    Last year, my parents moved to this town. I had to go to a new school and found no one to be friends with because I wasn't interested in the topics most of my classmates liked.

    “Maybe I'll never have real friends,” I thought. I closed my eyes and imagined playing my drums. Suddenly, I heard the sound of a guitar. I followed the sound and found out that was a band. I recognized(认出) the guitar player at my first sight and so did he. “Hey, you're Cassie from my class!” his voice surprised me.“I'm sorry,” I said. “I just haven't heard any live music in this town before! You sound great — did you guys write that song?”“Yeah — well, we're still working on it. I'm Matt.” He stood up and held out his hand.

    “Mind if I listen in?” I asked in a low voice. “Not at all,” Matt said, smiling. “Maybe you can give us some suggestions!”

    The song was pretty good and I could really improve it with my drum skills. Behind my drum set was the one place I felt completely like myself. But I wasn't sure if I wanted to open that door to the world.

    “Hey, do you play drums?” Matt asked suddenly. His question surprised me. How did he know? And then I followed his eyes to my hands, which had been beating a rhythm (节奏) on the floor. I tried to say no, but my heart stopped me from refusing. “Sure, I've been playing for a few years,” I said finally.“Oh, wow! You've got to join us!” Matt said. “I have some drums over here.”

    I looked at their shiny faces. “Clearly. I would love to play!” I replied. “One, two, three, four!” Matt counted and began singing, and I knew I was finally home.

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