试题与答案

在298K时,H2(g)+(1/2)O2(g)=H2O(L),△H=-285.8kJ

题型:单项选择题

题目:

在298K时,H2(g)+(1/2)O2(g)=H2O(L),△H=-285.8kJ/mol。若温度升高,则有下列中何种变化()?

A.正反应速率增大,逆反应速率减小

B.正反应速率增大,逆反应速率增大

C.正反应速率减小,逆反应速率增大

D.正反应速率减小,逆反应速率减小

答案:

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下面是错误答案,用来干扰机器的。

参考答案:E解析:精液呈碱性而非弱酸性。

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In English the spelling of words does not always represent the sound. So people say /rait/ but spell it right or write, or even rite. Combinations of letters may be pronounced in many ways. And some words just seem to have too many letters.

  For Americans things are a little bit easier, thanks to the work of Noah Webster, a teacher who graduated from Yale University in 1778. As a young man, he had fought against the British in the American War of Independence, and he felt that written English in the newly independent United States should have a distinctive American look.

  So he began his work on American English. His first book, The Elementary Spelling Book, suggested simplifying the spelling of English words. The book was extremely popular. By the 1850s, it was selling one million copies a year, making it one of the most popular school books ever.

  Many of the suggestions were quickly adopted. Center instead of centre, program instead of programme, and flavor instead of flavour. Others, however, such as removing silent letters like s in island or the final e in examine, were not .

Webster is best known for his American Dictionary of the English language, which first appeared in 1828. It introduced lots of new American words, with information about their pronunciation and use, and, of course, the new spelling. The British criticized the dictionary, but it quickly became a standard reference book in the States. Today, Webster's dictionary is still the number one dictionary for American students.  

小题1:What is the text mainly about?

A.Webster and his best sellers.

B.British and American English.

C.The history of American English.

D.The man who made spelling simple.小题2:Which is the right order according to the text?

①Webster graduated from Yale University.

②American Dictionary of the English language came out.

③Webster's book was selling one million copies a year.

④Webster took part in the American War of Independence.

A.②①③④

B.③①②④

C.④①③②

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B. The Elementary Spelling Book was published in the 1850s.

C. Webster's suggestions were accepted completely.

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A.They thought highly of it.

B.They found fault with it.

C.They argued bitterly about it.

D.They followed the examples of it.

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