欧美日韩黄网欧美日韩日B片|二区无码视频网站|欧美AAAA小视频|久久99爱视频播放|日本久久成人免费视频|性交黄色毛片特黄色性交毛片|91久久伊人日韩插穴|国产三级A片电影网站|亚州无码成人激情视频|国产又黄又粗又猛又爽的

相關(guān)習(xí)題
 0  52085  52093  52099  52103  52109  52111  52115  52121  52123  52129  52135  52139  52141  52145  52151  52153  52159  52163  52165  52169  52171  52175  52177  52179  52180  52181  52183  52184  52185  52187  52189  52193  52195  52199  52201  52205  52211  52213  52219  52223  52225  52229  52235  52241  52243  52249  52253  52255  52261  52265  52271  52279  211419 

科目: 來源: 題型:

(2009·揭陽)小紅在餐廳看到服務(wù)員用蓋子熄滅酒精燈火鍋,該滅火方法的主要原理是
A.清除可燃物B.降低可燃物的著火點(diǎn)
C.使可燃物的溫度降到著火D.隔絕空氣

查看答案和解析>>

科目: 來源: 題型:

(2009·北京)下圖所示的一組實(shí)驗(yàn)可用于研究燃燒條件。下列說法中,正確的是
A.此組實(shí)驗(yàn)燒杯中的熱水只起提高溫度的作用
B.圖1中水下白磷未燃燒是由于沒有與氧氣接觸
C.圖1實(shí)驗(yàn)不能比較白磷和紅磷的著火點(diǎn)高低
D.若將圖2中白磷換成紅磷,也能觀察到燃燒現(xiàn)象

查看答案和解析>>

科目: 來源: 題型:

(2009·綏化市)前不久大興安嶺局部地區(qū)發(fā)生森林火災(zāi),消防隊(duì)員緊急奔赴現(xiàn)場。他有的使用風(fēng)力滅火機(jī)強(qiáng)力滅火,其原理是                                   ;有的刊發(fā)部分樹木打防火用離帶,其滅火原理又是                           。

查看答案和解析>>

科目: 來源: 題型:

(2009·漳州市)學(xué)習(xí)化學(xué)后,我們可以用所學(xué)的化學(xué)知識回答生活中與化學(xué)相關(guān)的問題.。
(1)家用燃?xì)鉄崴鞑煌耆紵a(chǎn)生的主要有毒氣體是      。
(2)今年我市加大對九龍江水質(zhì)的整治力度,請你說出造成水質(zhì)污染的原因之一
                           。
(3)形成酸雨的原因是空氣受SO:和氮氧化合物的污染,酸雨給人類和環(huán)境帶來的危害有                           。
(4)某校九年級學(xué)生到郊外野炊,負(fù)責(zé)燒飯的同學(xué)引燃枯枝后,迅速往灶里塞滿枯枝,結(jié)果燃燒不旺,并產(chǎn)生了很多濃煙,原因是             ;活動結(jié)束后,同學(xué)們及時用水把火熄滅,其主要滅火原理是                          。

查看答案和解析>>

科目: 來源: 題型:

(2009·連云港市)2009年春節(jié)聯(lián)歡晚會上,劉謙的魔術(shù)表演激起了人們強(qiáng)烈的好奇心,并在全國范圍內(nèi)掀起了魔術(shù)表演的熱潮。在學(xué)?萍脊(jié)活動中,一位九年級同學(xué)給低年級同學(xué)表演了一組化學(xué)小魔術(shù),請你利用所學(xué)化學(xué)知識揭開其中之謎。

魔術(shù)一“奇花變色”
道具如圖25-1所示,該魔術(shù)中可觀察到“鐵樹”上浸有無色酚酞試液的棉團(tuán)由白色變?yōu)?u> ▲ 色。該魔術(shù)中沒有涉及的性質(zhì)是  ▲ (填字母序號)。
A.氨分子是不斷運(yùn)動的  B.氨分子有一定質(zhì)量  
C.濃氨水具有揮發(fā)性    D.氨氣的水溶液顯堿性
魔術(shù)二“瓶吞雞蛋”
道具如圖25-2所示,將注射器中NaOH濃溶液注入瓶中,片刻后會看到雞蛋被“吞”入瓶中。該魔術(shù)中涉及的化學(xué)反應(yīng)為  ▲ (用化學(xué)方程式表示)。
魔術(shù)三“水中生火”
道具如圖25-3所示,當(dāng)通過導(dǎo)管向熱水中通入氧氣時,白磷在水下燃燒。該魔術(shù)說明燃燒需要的條件為:①可燃物;②達(dá)到燃燒所需要的  ▲ ;③有充足的  ▲ 
魔術(shù)四“‘清水’變‘牛奶’”
道具如圖25-4所示,當(dāng)A溶液加到燒杯中,無色溶液變成白色濁液。若A為酸溶液,則A、B的可能組合:A為  ▲   ;B為  ▲ 。(只需寫一組)

查看答案和解析>>

科目: 來源: 題型:閱讀理解


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(詩), 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(標(biāo)簽) 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.
【小題1】
A.computerB.bikeC.carD.recorder
【小題2】
A.payB.buyC.supportD.a(chǎn)fford
【小題3】
A.signsB.factsC.marksD.results
【小題4】
A.HoweverB.FinallyC.QuietlyD.Actually
【小題5】
A.houseB.roomC.studyD.office
【小題6】
A.gaveB.handedC.showedD.presented
【小題7】
A.excitedB.nervousC.interestedD.disappointed
【小題8】
A.raisedB.changedC.improvedD.increased
【小題9】
A.ranB.wentC.walkedD.stormed
【小題10】
A.busyB.successfulC.comfortableD.happy
【小題11】
A.rememberedB.realizedC.knewD.considered
【小題12】
A.WhenB.AsC.AfterD.Before
【小題13】
A.informingB.a(chǎn)nnouncingC.tellingD.discovering
【小題14】
A.treasuresB.possessionsC.clothingD.eagerness
【小題15】
A.filledB.caughtC.a(chǎn)ttackedD.beat
【小題16】
A.pick upB.remind ofC.search throughD.refer to
【小題17】
A.seenB.gotC.leftD.thrown
【小題18】
A.madeB.writtenC.underlinedD.designed
【小題19】
A.droppedB.a(chǎn)ppearedC.rolledD.showed
【小題20】
A.yearB.dateC.momentD.Day

查看答案和解析>>

同步練習(xí)冊答案