不管化学反应过程是一步完成还是分为数步完成，这个过程的热效应_爱下问搜题

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问题选择题

不管化学反应过程是一步完成还是分为数步完成，这个过程的热效应是相同的。

已知：H₂O(g)===H₂O(l)　ΔH₁＝－Q₁ kJ·mol^－1①

C₂H₅OH(g)===C₂H₅OH(l)　ΔH₂＝－Q₂ kJ·mol^－1②

C₂H₅OH(g)＋3O₂(g)===2CO₂(g)＋3H₂O(g)　ΔH＝－Q₃ kJ·mol^－1③

若使23 g酒精液体完全燃烧，最后恢复到室温，则放出的热量为(　　)

A．(Q₁＋Q₂＋Q₃) kJ

B．[0.5(Q₁＋Q₂＋Q₃)] kJ

C．(0.5Q₁－1.5Q₂＋0.5Q₃) kJ

D．(1.5Q₁－0.5Q₂＋0.5Q₃) kJ

答案

答案：D

题目分析：根据盖斯定律，将【③式＋②式－（3×①式）】就得到46克酒精液体完全燃烧，最后恢复到室温的情况，将ΔH数值代入计算即可知道D选项正确。

点评：掌握盖斯定律的概念。

完形填空

Mr. Grey traveled a lot on business. He sold machines of different kinds to farmers. It was not really a very 36 job, but Mr. Grey had always been interested in 37 , and he was quite 38 with his life.
One of Mr. Grey’s problems was often__39___ to stay when he reached some small places in the country. He did not expect great ___40__ and wonderful food, but he found it annoying when he was given a __41___ room and when there was no hot water or good food after a long and ___42__ day.
Late one __43__ evening, Mr. Grey arrived at a small railway station. The journey by __44__ that day had not been ___45__ interesting, and Mr. Grey was cold and tired and hungry. He was __46___ a simple but satisfying meal by a bright burning __47___ , and then a hot bath and a comfortable ___48__.
While he was walking to the taxi stand, he said to a local man who was _ 49__ walking there, “ As this is my first __50___ to this part of the country and I was in too much of a __51___ to find out about hotels before I left home, I would very much like to know how many you have here?”
The local man answered, “ We have two.”
“And which of the two would you __52___ me to go to ?” Mr. Grey asked then.
The local man scratched his __53___ for a few moments and then answered, “ Well, it’s like this: ___54__ you go to, you’ll be ___55__ you didn’t go to the other.”

B．interesting

D．all the same

C．longing for

D．finding out

C．whichever one

D．neither one

多项选择题

系统结构的有序性具体表现在（）方面。

A.系统的边界

B.系统的层次

C.系统的整体性

D.系统的整合性