试题与答案

在25℃,101kPa下,1mol的白磷(化学式为P4)完全燃烧放出的热量比4m

题型:选择题

题目:

在25℃,101kPa下,1mol的白磷(化学式为P4)完全燃烧放出的热量比4mol的红磷(化学式为P)完全燃烧放出的热量多.反应方程式分别为:P4 (s)+5O2 (g)=P4O10 (s)    4P (s)+5O2 (g)=P4O10 (s)

由此判断,下列说法正确的是(  )

A.由红磷转化为白磷是吸热反应,等质量时红磷能量比白磷高

B.由红磷转化为白磷是放热反应,等质量时红磷能量比白磷低

C.由红磷转化为白磷是放热反应,等质量时红磷能量比白磷高

D.由红磷转化为白磷是吸热反应,等质量时红磷能量比白磷低

答案:

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参考答案:D

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三、完形填空(共20小题;每小题1.5分,满分30分)

Two Sundays ago,John was   36   in bed wondering whether to get up or not. He looked at his wrist but found that he wasn’t   37   his watch. Where on earth had he put it? He looked on the table and under the bed but he still couldn’t find it. He   38   think of anywhere else to look. “I must have   39   it in the bathroom or downstairs,” he thought to himself and lay down again for a moment.

Although he didn’t know the   40 ,he could hear the birds singing and see that the sun was shining. “I suppose I really ought to   41   up,” he thought. Mother must be   42   by now and I   43   her I’d help her clean the place up this morning.

After a while he heard his mother   44   upstairs. She came into the room and walked   45   to the window. “Good morning,dear.” she said。“I wonder if you’d get up now. It’s past nine o’clock and your aunt’s coming at ten. I’ve been   46   the cleaning since eight and I’ve   47   your breakfast. It’ll get cold   48   you don’t eat it now. Oh,   49   the way, you left your watch on the bathroom shelf and while I was cleaning it, it fell onto the floor and I think it’s   50   now. You’ll have to   51   it repaired. I’m afraid.”

“Oh, dear, I’m broken (没有钱的) just now. I can’t afford to get it fixed.”said John.

“Well, I’ve told you hundreds of times not to leave it in the   52 ,” said his mother. “  53  , never mind. I’ll pay for it. Come on now! I don’t want to   54   all day for you to get up.   55   you’ve had breakfast, perhaps you could do the washing up for me.”

36.A.laid   B.keeping    C.sitting       D.lying

37.A.dressing    B.wearing    C.having on D.putting on

38.A.mustn’t    B.shouldn’t  C.couldn’t    D.might not

39.A.left   B.forgotten  C.remembered     D.lost

40.A.moment    B.while C.when D.time

41.A.go     B.come C.get    D.stay

42.A.down       B.off    C.away D.up

43.A.promised  B.agreed      C.said   D.spoke

44.A.coming     B.running    C.going       D.rushing

45.A.out    B.down C.over  D.in

46.A.making     B.doing       C.having      D.starting

47.A.cooked     B.produced  C.did    D.had

48.A.unless       B.once  C.until  D.if

49.A.by     B.in      C.on     D.under

50.A.missing    B.gone  C.broken      D.lost

51.A.let     B.make C.have  D.had

52.A.reading room   B.bathroom  C.dining room     D.living room

53.A.But   B.So     C.Although  D.Because

54.A.waste       B.wait  C.spend       D.prepare

55.A.Before      B.After C.Since D.Before long

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