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问题 问答题

（9分）为解决过度使用化石燃料造成的能源危机及环境问题，科学家提出如下

图构想：

（1）水在催化剂和光照条件下分解可制得氢气，写出该反应的化学方程

式：                。

（2）垃圾中的有机物发酵得到沼气，写出沼气的主要成分燃烧的化学方程式：                   。

（3）科学家设想以燃烧产物中的CO2合成燃料CH3OH，这一反应可以缓解的环境问题是                   。

（4）氨气可在不同条件下与氧气反应生成不同的产物，且放出大量的热。若从环保角度考虑，氨气与氧气反应生成理想的产物是      和       。

答案

（9分）

光照

 
（1）2H2O 催化剂 2H2 ↑+O2 ↑ 。                                         

 

（2）CH4 + 2O2  点燃 CO2 + 2H2O 。

（3）温室效应（或酸雨等合理答案）。

（4）H2O和N2（或 “水和氮气”，顺序可调换）。

：（1）水在催化剂和光照条件下分解可制得氢气，反应的化学方程式为2H2O 催化剂 2H2 ↑+O2 ↑ 。                                         

（2）沼气的主要成分是甲烷，燃烧生成二氧化碳和水，反应的化学方程式为CH4 + 2O2  点燃 CO2 + 2H2O 。

（3）二氧化碳的增多，能使全球气候变暖，造成温室效应，以燃烧产物中的CO2合成燃料CH3OH，这一反应可以缓解温室效应；

（4）水不污染环境，氮气是空气的主要成分，也不污染空气，所以氨气与氧气反应生成理想的产物是H2O和N2．

故答案为：

光照

 
（1）2H2O 催化剂 2H2 ↑+O2 ↑ 。                                         

 

（2）CH4 + 2O2  点燃 CO2 + 2H2O 。

（3）温室效应（或酸雨等合理答案）。

（4）H2O和N2（或 “水和氮气”，顺序可调换）。

选择题

　　某一山岭，山麓B处与山顶A处的垂直高差为5000米。如果B处气温为20℃，则A处气温应该是多少摄氏度？[ ]

A．10℃

B．0℃

C．—10℃

D．50℃

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问答题

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