问题
选择题
下列物质在氧气中燃烧，生成黑色固体的是（ ）
A．木炭
B．硫磺
C．镁带
D．铁丝
答案
解；A、木炭在氧气中燃烧，生成无色气体，故A不符合题意；
B、硫磺在氧气中燃烧，生成刺激性的气体，故B不符合题意；
C、镁带在氧气中燃烧，生成白色固体，故C不符合题意；
D、铁丝在氧气中剧烈燃烧，火花四射，有黑色固体生成，故D符合题意．
故选D．
搜题请搜索小程序“爱下问搜题”
下列物质在氧气中燃烧，生成黑色固体的是（ ）
A．木炭
B．硫磺
C．镁带
D．铁丝
解；A、木炭在氧气中燃烧，生成无色气体，故A不符合题意；
B、硫磺在氧气中燃烧，生成刺激性的气体，故B不符合题意；
C、镁带在氧气中燃烧，生成白色固体，故C不符合题意；
D、铁丝在氧气中剧烈燃烧，火花四射，有黑色固体生成，故D符合题意．
故选D．
| 从方框中选择能填入对话中的正确选项。 | |
| A: Hello, Mrs White ! B: Hello, Mrs Wu! A: Are you going to do some shopping? B: Yes. What about you? A: 1______ It's said that (据说) the things in the new market are cheap and nice. I want to go there. 2______ B: That's good. 3______ A few Chinese ends will come to see me in an hour. I'm d I can't be back by then. A: It doesn't matter. We can go when we are free. B: By the way, 4______ I haven't been there yet. A: It's on the other side of the river. It's a little from here. B: How long does it take me to get there by bike? A: About a quarter. 5______ It'll take you right there. B: Thanks a lot. See you!
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