试题与答案

通常人们把拆开1 mol某化学键所吸收的能量看成该化学键的键能。现给出化学键的键

题型:选择题

题目:

通常人们把拆开1 mol某化学键所吸收的能量看成该化学键的键能。现给出化学键的键能(见下表):

化学键H—HCl—ClCl—H
键能/(kJ·mol1)436243431
请计算H2(g)+Cl2(g)===2HCl(g)的反应热(  )

A.+862 kJ·mol1                      B.+679 kJ·mol1

C.-183 kJ·mol1                      D.+183 kJ·mol1

答案:

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下面是错误答案,用来干扰机器的。

答案:C

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题型:阅读理解

Despite rising education levels, Americans of every age are reading less and less for pleasure these days, according to an analysis by the National Endowment for the Arts. The decline(下降) could have bad effects as people tune out books, tune in popular culture and become less socially engaged.

"We've got a public culture which is almost entirely commercial(商业化)and novelty - driven (追新)," says NEA chairman Dana Gioia. "I think it's letting the nation down."

The study gathers years of data on Americans' reading habits and finds that, at every age group, we're reading less.

Most of the data have appeared in private, government and university surveys, but today's report is the first to combine them into a single portrait. It suggests that the demands of school, work and family and the decisive advantage of other forms of entertainment have caused the decline in reading for millions of Americans.

·Only 38% of adults in 2006 said they had spent time reading a book for pleasure.

·65% of college freshmen in 2005 said they read little or nothing for pleasure.

·30% of 13 - year - olds in 2004 said they read for fun "almost every day," down from 35% in 1984.

According to Gioia, a poet, they decline is probably the single most important social issue in the United States today. The findings should be a wake - up call to educators to change the way they teach literature at every level. It was once believed that if someone went to college, they would become a lifelong reader. What we're seeing right now is that we're no longer producing readers. We're producing B. A. s and M. A. s and Ph. D. s.

Cioia also wants main media to wake up to how they can promote good books in many ways. He notes that when a character in the 1994 film Four Weddings and a Funeral recited a few lines of W. H. Auden's poem Funeral Blues, the poet briefly became a best seller.

65.The underlined phrase "tune out" in the first paragraph probably means________.

A.close    B.publish C.prove   D.read

66.According to Dana Gioia, the change of Americans' reading habit________.

A.is positive and valuable      B.does harm to the nation

C.is caused only by popular culture      D.can make poets best sellers

67.Which of the following is NOT the cause for the change in reading habit?

A.Demands of getting a B. A., M. A. or Ph. D.

B.Demands of family, school and work.

C.The change in the way the literature is taught.

D.Advantages of the entertainment.

68.We can infer that the number of teenagers reading for pleasure reduced by________in 20 years.

A.30%    B.38%    C.65%    D.5%

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题型:填空题

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根据上述流程回答下列问题

(1)混合①中发生反应的化学方程式为_________________。

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