题干

下列有关物质燃烧现象的叙述中,正确的是(   )

A:铁丝在氧气中燃烧:火星四射,生成红色固体

B:硫粉在空气中燃烧:产生淡蓝色火焰,生成一种刺激性气味的气体

C:镁条在空气中燃烧:发出耀眼的白光,只生成一种黑色固体

D:红磷在空气中燃烧:发出白光,生成大量的白色烟雾

上一题 下一题 0.0难度 选择题 更新时间:2017-11-23 07:09:47

答案(点此获取答案解析)

B

同类题1

阅读下面短文,请从每小题所给的A、B、C、D四个选项中选出最佳选项,并回答问题。

C

    Once upon a time,there was a king who had gone to visit neighboring kingdoms.He was gifted a pair of baby parrots by the king of the last kingdom where he was visiting.They were the most beautiful birds that he had ever seen.so,after returning to his kingdom,he called for a bird trainer and asked him to train parrots.

    The king also set up a place in the palace garden for the parrots.He often looked at them from his palace window.As time passed,one day the trainer came to the palace and told the king that though one of the parrots was flying high in the sky,the other one was not moving from its branch since the day it had arrived.

    When hearing this,the king summoned the best trainer from all his land and the nearby kingdoms.They came quickly and tried their best, but none of them could make the parrot fly!He even asked his courtiers to try to find a good way to make the parrot fly but they all failed.The parrot was not moving from his branch at all.Finally,after trying everything,the king thought to himself:"Perhaps I need someone who may be more familiar with natural habitat."He asked his courtier to get a farmer from the countryside and take him to the parrot to see if he could understand the problem with the parrot.

    The next morning,the king was surprised to see the parrot flying high above the palace gardens.He asked his servant to call that farmer to meet him.The servant quickly went and found the farmer.The farmer came and stood before the king.The king asked him,"How did you make the parrot fly?" With his hands folded with respect,the farmer said to the king,"It was very easy.I just cut the branch where the bird was sitting."