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(2009·揭阳)小红在餐厅看到服务员用盖子熄灭酒精灯火锅,该灭火方法的主要原理是
A.清除可燃物B.降低可燃物的着火点
C.使可燃物的温度降到着火D.隔绝空气

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(2009·北京)下图所示的一组实验可用于研究燃烧条件。下列说法中,正确的是
A.此组实验烧杯中的热水只起提高温度的作用
B.图1中水下白磷未燃烧是由于没有与氧气接触
C.图1实验不能比较白磷和红磷的着火点高低
D.若将图2中白磷换成红磷,也能观察到燃烧现象

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(2009·绥化市)前不久大兴安岭局部地区发生森林火灾,消防队员紧急奔赴现场。他有的使用风力灭火机强力灭火,其原理是                                   ;有的刊发部分树木打防火用离带,其灭火原理又是                           

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(2009·漳州市)学习化学后,我们可以用所学的化学知识回答生活中与化学相关的问题.。
(1)家用燃气热水器不完全燃烧产生的主要有毒气体是      
(2)今年我市加大对九龙江水质的整治力度,请你说出造成水质污染的原因之一
                           
(3)形成酸雨的原因是空气受SO:和氮氧化合物的污染,酸雨给人类和环境带来的危害有                           
(4)某校九年级学生到郊外野炊,负责烧饭的同学引燃枯枝后,迅速往灶里塞满枯枝,结果燃烧不旺,并产生了很多浓烟,原因是             ;活动结束后,同学们及时用水把火熄灭,其主要灭火原理是                          

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(2009·连云港市)2009年春节联欢晚会上,刘谦的魔术表演激起了人们强烈的好奇心,并在全国范围内掀起了魔术表演的热潮。在学校科技节活动中,一位九年级同学给低年级同学表演了一组化学小魔术,请你利用所学化学知识揭开其中之谜。

魔术一“奇花变色”
道具如图25-1所示,该魔术中可观察到“铁树”上浸有无色酚酞试液的棉团由白色变为 ▲ 色。该魔术中没有涉及的性质是  ▲ (填字母序号)。
A.氨分子是不断运动的  B.氨分子有一定质量  
C.浓氨水具有挥发性    D.氨气的水溶液显碱性
魔术二“瓶吞鸡蛋”
道具如图25-2所示,将注射器中NaOH浓溶液注入瓶中,片刻后会看到鸡蛋被“吞”入瓶中。该魔术中涉及的化学反应为  ▲ (用化学方程式表示)。
魔术三“水中生火”
道具如图25-3所示,当通过导管向热水中通入氧气时,白磷在水下燃烧。该魔术说明燃烧需要的条件为:①可燃物;②达到燃烧所需要的  ▲ ;③有充足的  ▲ 
魔术四“‘清水’变‘牛奶’”
道具如图25-4所示,当A溶液加到烧杯中,无色溶液变成白色浊液。若A为酸溶液,则A、B的可能组合:A为  ▲   ;B为  ▲ 。(只需写一组)

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科目: 来源: 题型:阅读理解


A young man was getting ready to graduate from college. He had wanted a beautiful  1  in a dealer’s showroom, and knowing his father could well   2  it, he told him that was all he wanted.
As Graduation Day came near, the young man expected   3   that his father had bought the gift.   4 , on the morning of his graduation, his father called him into his own   5 . His father told him how proud he was to have such a fine son, and told him how much he loved him. He   6  his son a beautifully wrapped gift box. Curious, and somewhat   7 , the young man opened the box and found a lovely leather bound Bible,with the young man’s name written in gold. Angry, he  8  his voice to his father, and said, “With all your money you give me a Bible?” and  9   out of the house.
Many years passed and the young man was very   10  in business. He had a beautiful home and wonderful family, but   11  his father was very old, and thought perhaps he should go to see him.   12  he could make arrangements, he received a telegram   13  him his father had passed away and willed all of his 14  to his son. When he arrived at his father’s, sudden sadness and regret   15 his heart. He began to   16  his father’s important papers and saw the still new gift-wrapped Bible, just as he had   17  it years ago. With tears, he opened the Bible and began to turn the pages. His father had carefully   18  a verse(诗), Matthew 7-11,“And if you, being evil, know how to give good gifts to your children, how much more shall your Heavenly Father which is in Heaven, give to those who ask Him?”
As he read those words, a car key  19  from the back of the Bible. It had a tag(标签) with the dealer’s name, the same dealer who had the sports car he had desired. On the tag was the   20  of his graduation, and the words: PAID IN FULL.
【小题1】
A.computerB.bikeC.carD.recorder
【小题2】
A.payB.buyC.supportD.afford
【小题3】
A.signsB.factsC.marksD.results
【小题4】
A.HoweverB.FinallyC.QuietlyD.Actually
【小题5】
A.houseB.roomC.studyD.office
【小题6】
A.gaveB.handedC.showedD.presented
【小题7】
A.excitedB.nervousC.interestedD.disappointed
【小题8】
A.raisedB.changedC.improvedD.increased
【小题9】
A.ranB.wentC.walkedD.stormed
【小题10】
A.busyB.successfulC.comfortableD.happy
【小题11】
A.rememberedB.realizedC.knewD.considered
【小题12】
A.WhenB.AsC.AfterD.Before
【小题13】
A.informingB.announcingC.tellingD.discovering
【小题14】
A.treasuresB.possessionsC.clothingD.eagerness
【小题15】
A.filledB.caughtC.attackedD.beat
【小题16】
A.pick upB.remind ofC.search throughD.refer to
【小题17】
A.seenB.gotC.leftD.thrown
【小题18】
A.madeB.writtenC.underlinedD.designed
【小题19】
A.droppedB.appearedC.rolledD.showed
【小题20】
A.yearB.dateC.momentD.Day

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