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问题 问答题

煤化工是指在一定条件下将煤等物质转化为H2、CO和炭黑等一系列重要化工原料的生产过程．

（1）用炭黑制成的墨汁书写或绘制的字匮能够经久不变色，其原因是______；

（2）将干燥的H2和CO两种气体分别点燃，在火焰上方各罩一个冷而干燥的烧杯，烧杯内壁出现水雾或水珠的原气体是______

（3）CO是一种气体燃料，其燃烧的化学方程式为2CO+O2=2CO2．烧水或做饭时，人不要远离灶具，如果火焰熄灭而又没有及时关闭燃气灶，可燃性气体会在厨房里扩散，遇明火会发生______的危险．

答案

（1）碳的化学性质常温下很稳定，在生活中有很多方面利用了碳的稳定性，如用炭黑制成的墨汁书写或绘制字匮，可以经久不变色，故答案为：常温下碳的化学性质稳定

（2）氢气燃烧生成的水蒸遇冷凝结成小水珠，可以证明水的生成，故答案为：H2

（3）CO是一种可燃性气体，混有空气遇明火会发生爆炸，故答案为：爆炸

阅读理解

The NBA playoffs(季后赛) began on April 28, and the next two months will be filled with games decided in the final minutes. The playoffs are also a way to show off the world’s best basketball players.
There’s a saying from Spiderman: “With great power comes great responsibility(责任).” This is true no matter whether you are a class monitor or a president. A recent survey in the USA asked kids what they would do to make life better for other kids if they were president. “Providing shelter” topped the list.
May 19, 1613: Xu Xiake, a famous traveler during the Ming Dynasty, started his trip around China, which lasted for more than 30 years. In 2011, China announced its first National Tourism Day, held on May 19 every year in memory of this ancient explorer.
Do you have female friends that refer to as “guimi”? If you are a girl and the answer is yes, you are a lucky dog. “Guimi” is only used among girls. It refers to your most honest friends. In English, the word to use is “BFF”- which stands for best friend forever. But if you want to say a guy is your close friend or “nanguimi”, you should use “bromeo”, which is made up of “bro” and “Romeo”.
CHINA is planning to build a national earthquake monitoring and warning system in five years. While the system would never be able to forecast an earthquake, it could detect(探测) quakes and notify people within seconds before seismic(地震引起的) waves actually hit them, and a trial program including nearly 100 monitoring stations is currently being carried out in southeast China’s Fujian Province and has proven successful.
小题1:The above five passages may be         .
A．from posters B．from newspapers C．from adsD．from novels
小题2:From the passage we know May 19 is           in China.
A．the beginning of the NBA playoffs B．in memory of Spiderman
C．Earthquake DayD．National Tourism Day
小题3:“Guimi” refers to           .
A．any female friendsB．bromeoC．your most honest friendsD．those friends who can only share happiness
小题4:China’s earthquake monitoring and warning system could           .
A．forecast an earthquake B．be used in Zhejiang Province
C．not detect quakesD．notify people within seconds
小题5:Which of the following is wrong according to the passage?
A．China will build earthquake warning system in five years.
B．In English, the word “BFF” stands for best friend forever.
C．The playoffs can show off the world’s best football players.
D．“Providing shelter” topped the list in American kids’ survey.
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问答题 简答题

循环流化床锅炉尾部烟道受热面积灰有何危害？
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