下列关于实验现象的描述不正确的是（ ）
A．铁丝在氧气中燃烧发出白光，生成黑色固体
B．硫在空气中燃烧发出淡蓝色的火焰
C．家庭小实验中，将食醋与纯碱混合有大量气泡产生
D．将生铁粉末投入盛有过量盐酸的烧杯中，充分反应后仍有黑色残渣
A、铁丝在氧气中燃烧火星四射，不是发出白光，故A错误；
B、硫在空气中燃烧发出淡蓝色的火焰，故B正确；
C、食醋含醋酸，纯碱是碳酸钠，碳酸钠能与醋酸反应生成二氧化碳，故C正确；
D、生铁是铁与碳的合金，投入盐酸中，铁参与反应，而碳不与盐酸反应，故D正确，
故选A．
Do you have lots of friends? What do you 36 friends and friendship? Are they very important for you? Some of your friends may have different views and interests, and some like doing the same 37 as you. Do you like friends different from 38 the same as you? You may like the friends who 39 the same interests as you. But I don’t really care. I have two good friends, Peter and James. Peter is 40 me. I am a quiet boy, and Peter is also quiet. We 41 enjoy reading books and surfing the Internet. On weekends, we often go to the library or 42 on the computer together. But James is very different from us. He likes playing ball games, and he is more athletic than us. He is 43 more outgoing. He likes talking and often makes 44 laugh. You see, friends are not 45 to be the same. Do you agree with me?
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