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问题 选择题

已知

⑴ H2(g)＋1/2 O2(g)====H2O(g) ； △H1＝a kJ·mol-1

⑵ 2H2(g)+ O2(g)===2H2O(g) ； △H2＝b kJ·mol-1

⑶ H2(g)＋1/2O2(g)====H2O(l) ； △H1＝c kJ·mol-1

⑷ 2H2(g)+ O2(g)===2H2O(l) ； △H2＝d kJ·mol-1

下列关系式中正确的是[ ]

A．a＜b＜0

B．b＞d＞0

C．2a=b＜0

D．2c=d＞0

答案

答案：C

阅读理解
阅读下面A-E五段叙述, 并将其与56-60五个主题说明分别匹配.
Reading Tips (suggestions)

A. Have everything ready:
●  something to read
●  marker to highlight(标出) difficult words
●  dictionary
●  your vocabulary book
●  pen to write down the new words
B. Choose a magazine or a book about a subject that you like, because you are going to spend time and
     money on it. You can also read newspapers.
C. Read something that you can, more or less, understand. If you need to stop every three words to look
     in a dictionary, it will not be interesting for you and you will soon feel frustrated.
D. For example, read for a short time once a day. Fifteen minutes every day is better than two hours every
     Sunday. Set time to read and keep to it. For example, you could read for fifteen minutes before you go
     to bed, or when you get up, or at lunchtime.
E. If there  are four or  five new words on a  page, write them in your  vocabulary book. But don't  write
    them while you read. Instead, as you read, try to guess their meanings first. Mark them with a pen and
    then come back for them after you have finished reading. Then you can check in a  dictionary  before
    you add them in your vocabulary book.

(   ) 1. Try to read at the right level(水平)
(   ) 2. Make a note of new vocabulary
(   ) 3. Try to read regularly (often)
(   ) 4. Be organized
(   ) 5. Read what interests you
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单项选择题

与苯丙胺有关的描述不正确的是（）

A.具有强烈的中枢神经兴奋作用和致欣快作用

B.中毒时可出现幻觉、妄想症状

C.与可卡因有类似的药理作用

D.使用后很快体会到快感

E.极易产生躯体依赖和精神依赖
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