题干

氨基钠(NaNH2)是合成维生素A的原料。工业上将金属钠于97~100℃熔融,向反应器中缓慢通入无水液氨(NH3),再加热至350~360℃生成氨基钠(NaNH2)和氢气。下列说法中,不正确的是(   )

A:钠可能与水反应

B:钠的熔点比铁的熔点低

C:维生素A中一定含有钠元素

D:反应的化学方程式为:2Na+2NH32NaNH2+H2

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C

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    My parents used to tell me how important the school was for me, but I didn’t think so. I didn’t   1    it. What I cared most was to hang out with my friends. But one thing let me finally  2  what my parents meant.

    One day, when I walked3a cellphone store, I saw an advertisement on its door. It was hiring(雇佣) new workers!

    “Sir, are you hiring people?” I went into the shop and asked. “Yes, but you  4 be the man who we need.” the manager answered. He looked at me for a few minutes from head to 5 .” Do you have a high school diploma(文凭)?”he asked, “do you have any working  6 ?”

    I felt so ashamed and  7  that I didn’t know what to say, so I just turned around and left.

I could not fall asleep that night, and I thought a lot about my future. “I must go to school  8  I can’t do anything without a good education,” I said to myself. I never went back to the store9  before I finished my study and got a diploma.

    Everything looked the same when I returned to the10: the same people and the same design. However,  11 with last time, I had more confidence this time. So it was a great chance for me.

I12  my diploma to the manager who once refused me. He looked at  13 for a while and then said to me, “Great, you are in.”

    Now I am still working in the same store. With this experience, I  14advise teenagers to attend to school. Education helps you have a bright future. Now I am not worried about my future because I still keep 15  in my free time. Education brings my future, doesn’t it?