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问题 不定项选择题

已知反应2H2(g) + O2(g) ==2H2O (1) △H=-285．8 kJ·mol-1，下列结论中，正确的是 [ ]

A．E(反应物)>E(生成物)

B．E(反应物)<E(生成物)

C．反应放热

D．反应吸热

答案

AC

写作题

保护好我们的生活环境是一件非常重要的事情，请根据以下表格提示, 以How to Protect the Environment为题写一篇100字左右的短文，阐明你的观点，并把答案转写在答题卡上, 短文开头已给出，不计入短文字数。

Problems    Factories and cars give off (放出)poisonous(有毒的) gas;

Trees are cut down;

Waste water is poured into(被倒入) river;

Rubbish is thrown everywhere;

…

Measures    take measures :for example: make laws to stop pollution …

Your opinions   make people aware of the importance of protecting the environment;

To protect the environment is to protect ourselves…

Environmental problems are becoming more and more serious all over the world. For example, ________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
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单项选择题

通电试验的顺序是（）。

A.先高压电路后低压电路

B.先低压电路后高压电路

C.先摄影电路后透视电路

D.先灯丝加热电路后电源电路

E.以上都不是
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