题干

在某密闭容器中有16L NO和 NH3的混合气体,在催化剂和加热条件下发生     如下反应: 6NO + 4NH  6 H2O + 5N2,当各物质的浓度不随时间变化时,混合气体的体积为17L,则原混合气体中NO和 NH3的体积之比为
①3:5  ②3:4   ③3:2  ④3:1

A:①④

B:②③

C:①②

D:③④

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B

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    When I was growing up in America, I was ashamed of my mother's Chinese English. Because of her English, she was often treated unfairly. People in department stores, at banks, and at restaurants did not take her seriously, pretended(假装) not to understand her, or even acted as if they did not hear her.
    My mother has realized the disadvantages of her English as well. When I was fifteen, she used to have me call people on phone to pretend I was she. I was forced to ask for information or even to yell at people who had been rude to her. One time I had to call her stockbroker(股票经纪人). I said in a voice that was not very convincing, “This is Mrs. Tan.” And my mother was standing beside me, whispering loudly, “Why he doesn't send me the check. It's already two weeks late.”
    And then, in perfect English I said: “I'm getting rather anxious .You agreed to send the check two weeks ago, but it hasn’t arrived.” Then she talked more loudly. “What does he want? I’ll come to New York and say it in front of his boss.” And so I turned to the stockbroker again, “I can't accept any more excuses. If I don’t receive the check immediately, I have to speak to your manager when I am in New York next week.”
    The next week we ended up in New York. While I was sitting there red-faced, my mother, the real Mrs. Tan, was shouting to his boss in her broken English. When I was a teenager, my mother’s broken English embarrassed (使困窘) me. But now, I see it differently. To me, my mother’s English is perfectly clear, perfectly natural. It is my mother tongue. Her language, as I hear it, is clear and direct. It was the language that helped me form the way I saw things, expressed ideas, and made sense of the world.