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若，均为非零向量，则•＝||||是与共线的（ ）
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高二上学期数学《》真题及答案
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下列说法中错误的是
零向量与任一非零向量平行
零向量与单位向量的模不相等
平行向量的方向相同
平行向量一定是共线向量
设两个非零向量不共线且共线则k的值为.
非零向量a＝sinθ2b＝cosθ1若a与b共线则tanθ－＝________.
命题零向量与任意向量共线的否定为
在以下3个命题中真命题的个数是①三个非零向量abc不能构成空间的一个基底则abc共面②若两个非零向量
0
1
2
3
在如图所示的方格纸中向量abc的起点和终点均在格点小正方形顶点上若c与xa+ybxy为非零实数共线则
设ab是两个不共线的非零向量若a与b起点相同t∈R.t为何值时atba＋b三向量的终点在一条直线上
已知非零向量a和b不共线.1若=a+b=2a+8b=3a-b求证A.B.D.三点共线2若ka+b和a
在下列判断中正确的是①长度为0的向量都是零向量②零向量的方向都是相同的③单位向量的长度都相等④单位向
①②③
②③④
①②⑤
①③⑤
以下说法错误的是
零向量与任一非零向量平行
零向量与单位向量的模不相等
平行向量方向相同
平行向量一定是共线向量
命题零向量与任意向量共线的否定为__________________________________
非零向量不共线使共线的k=___________
设ab是不共线的两个非零向量.1若=2a-b=3a+b=a-3b求证A.B.C.三点共线2若8a+k
设两个非零向量a与b不共线.1若＝3a－b.求证A.B.D.三点共线2试确定实数k使ka＋b和a＋k
非零向量不共线使共线的k=___________
下列说法不正确的是
向量的模是一个非负实数
任何一个非零向量都可以平行移动
长度不相等而方向相反的两个向量一定是共线向量
两个有共同起点且共线的向量终点也必相同
以下说法错误的是
零向量与任一非零向量平行
零向量与单位向量的模不相等
平行向量方向相同
平行向量一定是共线向量
若ab是两个不共线的非零向量a与b的起点相同则当t为何值时atba＋b三向量的终点在同一条直线上
若ab均为非零向量则a·b＝|a||b|是a与b共线的
充分不必要条件
必要不充分条件
充要条件
既不充分也不必要条件
已知两个非零向量e1e2不共线若ke1+e2与e1+ke2也不共线则实数k满足的条件是
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碳氮硫是中学化学重要的非金属元素在工农业生产中有广泛的应用． 1用于发射“天宫一号”的长征二号火箭的燃料是液态偏二甲肼CH32N﹣NH2氧化剂是液态四氧化二氮．二者在反应过程中放出大量能量同时生成无毒无污染的气体．已知室温下1g燃料完全燃烧释放出的能量为42.5kJ请写出该反应的热化学方程式． 2298K时在2L的密闭容器中发生可逆反应2NO2g⇌N2O4g△H＝﹣akJ•mol﹣1a＞0．N2O4的物质的量浓度随时间变化如图1．达平衡时N2O4的浓度为NO2的2倍回答下列问题． ①298k时该反应的平衡常数为． ②在温度为T1T2时平衡体系中NO2的体积分数随压强变化曲线如图2所示．下列说法正确的是 a．AC两点的反应速率A＞C b．BC两点的气体的平均相对分子质量B＜C c．AC两点气体的颜色A深C浅 d．由状态B到状态A可以用加热的方法 ③若反应在398K进行某时刻测得nNO2＝0.6molnN2O4＝1.2mol则此时V正V逆填“＞”“＜”或“＝”． 3NH4HSO4在分析试剂医药电子工业中用途广泛．现向100mL0.1mol•L﹣1NH4HSO4溶液中滴加0.1mol•L﹣1NaOH溶液得到的溶液pH与NaOH溶液体积的关系曲线如图3所示．试分析图中abcde五个点 ①水的电离程度最大的是 ②其溶液中cOH﹣的数值最接近NH3•H2O的电离常数K数值的是 ③在c点溶液中各离子浓度由大到小的排列顺序是．
设NA为阿伏加德罗常数的值．下列说法正确的是
锌是一种应用广泛的金属目前工业上主要采用湿法工艺冶炼锌某含锌矿的主要成分为ZnS还含少量FeS等其他成分以其为原料冶炼锌的工艺流程如图所示回答下列问题1硫化锌精矿的焙烧在氧气气氛的沸腾炉中进行所产生焙砂的主要成分的化学式为．2焙烧过程中产生的含尘烟气可净化制酸该酸可用于后续的操作．3浸出液净化过程中加入的主要物质为其作用是．4电解沉积过程中的阴极采用铝板阳极采用Pb﹣Ag合金惰性电极阳极逸出的气是．5改进的锌冶炼工艺采用了氧压酸浸的全湿法流程既省略了易导致空气污染的焙烧过程又可获得一种有工业价值的非金属单质．氧压酸浸中发生主要反应的离子方程式为．6我国古代曾采用火法工艺冶炼锌明代宋应星著的天工开物中有关于升炼倭铅的记载炉甘石十斤装载入一泥罐内然后逐层用煤炭饼垫盛其底铺薪发火煅红冷淀毁罐取出即倭铅也．该炼锌工艺过程主要反应的化学方程式为．注炉甘石的主要成分为碳酸锌倭铅是指金属锌
已知1CH3COOHl+2O2g＝2CO2g+2H2Ol△H1 2Cs+O2g＝CO2g△H2 32H2g+O2g＝2H2Ol△H3 42CO2g+4H2g＝CH3COOHl+2H2Ol△H4 52Cs+2H2g+O2g＝CH3COOHl△H5 下列关于上述反应的焓变的判断正确的是
Hundredsofpeoplehaveformedimpressionsofyouthroughthatlittledevice装置onyourdesk.Andthey'veneveractually41you.Everythingtheyknowaboutyou42throughthisdevicesometimesfromhundredsofmilesaway.43heyfeeltheycanknowyou44fromthesoundofyourvoice.That'showpowerfulthe45is.Powerfulyesbutnotalways46.ForyearsIdealtwithmytravelagentonlybyphone.RanimyfacelessagentwhomI'dnevermet47gotmerock﹣bottompricesonairfarescarsandhotels.Buthercoldvoicereally48me.Isometimeswishedto49anotheragent.OnemorningIhadto50animmediateflighthomeforafamilyemergency.IranintoRani'soffice51.Thewomansittingatthedesk52mymadnesssympatheticallyjumpedup.Shegavemea53smilenoddedwhilelisteningpatientlyandthenprintedoutthe54immediately.'Whatawonderfullady!'Ithought.Rushingout55Icalledoutovermyshoulder'Bythewaywhat'syourname?''I'mRani'shesaid.Iturnedaroundandsawa56womanwithabigsmileonherfacewavingtowishmeasafetrip.Iwas57!WhyhadIthoughtshewascold?Raniwaswellso58.SittingbackinthecaronthewaytotheairportIfigureditallout.Rani's59﹣﹣﹣herwarmsmilehernodsher‘I'mhereforyou'60﹣﹣﹣wereallsilentsignalsthatdidn'ttravelthroughwires.41.A.accepted B.noticed C.heard D.met42.A.came B.moved C.ran D.developed43.A.Thus B.Yet C.Then D.Indeed44.A.rather B.also C.just D.already45.A.Telephone B.voice C.connection D.impression46.A.direct B.useful C.easy D.accurate47.A.inperson B.bymyself C.inpublic D.onpurpose48.A.annoyed B.interested C.discouraged D.confused49.A.promote B.train C.find D.know50.A.arrange B.postpone C.confirm D.book51.A.forthefirsttime B.atanytime C.fromtimetotime D.ingoodtime52.A.expecting B.seeing C.testing D.avoiding53.A.shy B.comforting C.familiar D.forced54.A.bill B.form C.ticket D.list55.A.hopefully B.disappointedly C.gratefully D.regretfully56.A.careful B.serious C.nervous D.pleasant57.A.amused B.worried C.helpless D.speechless58.A.calm B.nice C.proud D.clever59.A.forgiveness B.eagerness C.friendliness D.skillfulness60.A.explanation B.attitude C.concept D.Behavior
AnewcollectionofphotosbringsanunsuccessfulAntarcticvoyagebacktolife.FrankHurley'spictureswouldbeoutstanding﹣﹣﹣﹣undoubtedlyfirst﹣ratephoto﹣journalism﹣﹣﹣iftheyhadbeenmadelastweek.Infacttheywereshotfrom1914through1916mostofthemafteradisastrousshipwreck海难byacameramanwhohadnoreasonableexpectationofsurvival.Manyoftheimageswerestoredinanicechestunderfreezingwaterinthedamagedwoodenship.TheshipwastheEnduranceasmalltightNorwegian﹣builtthree﹣masterthatwasintendedtotakeSirErnestShackletonandasmallcrewofseamenandscientists27meninalltothesouthernmostshoreofAntarctica'sWeddellSea.FromthatpointShackletonwantedtoforceapassagebydogsled雪橇acrossthecontinent.ThejourneywasintendedtoachievemorethanwhatCaptainRobertFalconScotthaddone.CaptainScotthadreachedtheSouthPoleearlyin1912buthaddiedwithhisfourcompanionsonthemarchback.AswriterCarolineAlexandermakesclearinherforcefulandwell﹣researchedstoryTheEnduranceadventuringwaseventhenathoroughlycommercialeffort.Scott'slastjourneycompletedasbelayinatentdyingofcoldandhungercaughttheworld'simaginationandafilmmadeinhishonordrewcrowds.ShackletonaonetimeBritishmerchant﹣navyofficerwhohadgottowithin100milesoftheSouthPolein1908startedabusinessbeforehis1914voyagetomakemoneyfrommovieandstillphotography.FrankHurleyaconfidentandgiftedAustralianphotographerwhoknewtheAntarcticwashiredtomaketheimagesmostofwhichhaveneverbeforebeenpublished.33.WhatdoweknowaboutthephotostakenbyHurley?A.TheyweremadelastweekB.TheyshowedunderseasceneriesC.TheywerefoundbyacameramanD.Theyrecordedadisastrousadventure34.WhoreachedtheSouthPolefirstaccordingtothetext?A.FrankHurleyB.ErnestShackletonC.RobertFalconScottD.CarolineAlexander35.WhatdoesAlexanderthinkwasthepurposeofthe1914voyage?A.ArtisticcreationB.ScientificresearchC.MoneymakingD.Treasurehunting.
Mr.Obama_____PresidentoftheUnitedStatesmustface____realitythatthecountry'seconomyisslidingbackward. A./the B.thethe C.// D.thea
10分WhenIwasakidMomusedtocookfoodforus.Onenightinparticularafter1spendalongharddayatworkMomplacedaplateofbreadjamand2extremeburnttoastinfrontofmydad.Iwaswaiting3seeifanyonenoticedit.ButwhileeatinghistoastDadjustaskedme4mydaywasatschoo1.Idon'trememberwhatItoldhimthatnight5IdorememberIheardMomapologizingtoDadforburningthetoast.AndI'llneverforgetwhathesaid'HoneyIloveburnttoast.'LaterthatnightI6gotokissDaddygoodnightandaskedhimifhereallylikedhistoastburned.Hegaveme7bighugandsaid'Yourmammaputinalongharddayatworktodayreally8tire.Andbesidesaburnttoastneverhurtsanyonebutcoldwordsdo!'WhatI'velearnedovertheyears9bethatlearningtoaccepteachother'sfaultsisoneofthemostimportant10keytocreatingahealthygrowingandlastingrelationship.
What'sOn?ElectricUnderground7.30pm﹣1.00amFreeattheCyclopsTheatreDoyouknowwho'splayinginyourarea?We'rebringingyouaneveningofliverockandpopmusicfromthebestlocalbands.Areyouinterestedinbecomingamusicianandgettingarecordingcontract合同?Ifsocomeearlytothetalkat7.30pmbyJulesSkyeasuccessfulrecordproducer.He'sgoingtotalkabouthowyoucanfindtherightpersontoproduceyoumusic.GeeWhizz8.30pm﹣10.30pmComedyatKaleidoscopeComeandseeGeeWhizzperform.He'sthefunnieststand﹣upcomedianonthecomedyscene.Thisjoyfulshowwillpleaseeveryonefromtheyoungesttotheoldest.GeeWhizzreallyknowshowtomakeyoulaugh!Ourbarisopenfrom7.00pmfordrinksandsnacks快餐.Simon'sWorkshop5.00pm﹣7.30pmWednesdaysatVictoriaStageThisisagoodchanceforanyonewhowantstolearnhowtodocomedy.Theworkshoplooksateverykindofcomedyandpracticesmanydifferentwaysofmakingpeoplelaugh.Simonisacomedianandactorwhohas10years'experienceofteachingcomedy.Hisworkshopsareexcitingandfun.AneveningwithSimonwillgiveyoutheconfidencetobefunny.CharlotteStone8.00pm﹣11.00pmPizzaWorldFinefoodwithbeautifuljazzmusicthisisagreateveningout.CharlotteStonewillperformsongsfromhernewbest﹣sellingCDwithJamesPickeringonthepiano.ThemenuisItalianwithexcellentmeatandfreshfishpizzasandpasta面食.Bookearlytogetatable.Ourbarisopenalldayandservescocktailscoffeebeerandwhitewine.21.Whocanhelpyouifyouwanttohaveyourmusicproduced?A.JulesSkye.B.GeeWhizz.C.CharlotteStone.D.JamesPickering.22.Atwhichplacecanpeopleofdifferentagesenjoyagoodlaugh?A.TheCyclopsTheatreB.KaleidoscopeC.VictoriaStageD.PizzaWorld23.WhatdoweknowaboutSimon'sWorkshop?A.Itrequiresmembershipstatus.B.Itlaststhreehourseachtime.C.Itisrunbyacomedyclub.D.ItisheldeveryWednesday.24.WhenwillCharlotteStoneperformhersongs?A.5.00pm﹣7.30pm.B.7.30pm﹣1.00am.C.8.00pm﹣11.00pm.D.8.30pm﹣10.30pm.
下列有关化学用语表示正确的是
假定你是李华你校摄影俱乐部photographyclub将举办国际中学摄影展.请给你的英国朋友Peter写封信.请他提供作品.信的内容包括 1.主题环境保护 2.展览时间 3.投稿邮箱intlphotoshow@gmschool.com. 注意 1.词数100左右 2.可以适当增加细节以使行文连贯.
假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.每处错误仅涉及一个单词的增加删除或修改. 增加在缺词处加一个漏字符号Λ并在其下面写出该加的词. 删除把多余的词用斜线﹨划掉. 删除在错的词下划一横线并在该词下面写出修改后的词. 注意1.每处错误及其修改均仅限一词 2.只允许修改10处多者从第11处起不计分. Thesummerholidayiscoming.MyclassmatesandIaretalkingabouthowtododuringtheholiday.Wecanchosebetweenstayingathomeandtakeatrip.Ifwestayathomeitiscomfortablebutthereisnoneedtospendmoney.Butinthatcasewewilllearnlittleaboutworld.Ifwegoonatripabroadwecanbroadenyouviewandgainknowledgeswecannotgetfrombooks.Someclassmatessuggestwecangotoplacesofinterestnearby.Ithoughtthatitisagoodidea.Itdoesnotcostmanyyetwecanstilllearnalot.
氮磷及其化合物在科研及生产中均有着重要的应用． 1某课外学习小组欲制备少量NO气体写出铁粉与足量稀硝酸反应制备NO的离子方程式 2LiFePO4是一种新型动力锂电池的电极材料． ①图1为某LiFePO4电池充放电时正极局部放大示意图写出该电池放电时正极反应方程式． ②将LiOHFePO4•2H2O米白色固体与还原剂葡萄糖按一定计量数混合在N2中高温焙烧可制得锂电池正极材料LiFePO4．焙烧过程中N2的作用是实验室中以Fe3+为原料制得的FePO4•2H2O有时显红褐色FePO4•2H2O中混有的杂质可能为． 3磷及部分重要化合物的相互转化如图2所示． ①步骤Ⅰ为白磷的工业生产方法之一反应在1300℃的高温炉中进行其中SiO2的作用是用于造渣CaSiO3焦炭的作用是． ②不慎将白磷沾到皮肤上可用0.2mol/LCuSO4溶液冲洗根据步骤Ⅱ可判断1molCuSO4所能氧化的白磷的物质的量为． ③步骤Ⅲ中反应物的比例不同可获得不同的产物除Ca3PO42外可能的产物还有．
Ifyoufeelstressedbyresponsibilitiesatworkyoushouldtakeastepbackandidentify识别thoseof61greatandlessimportance.Thenhandlethemostimportanttasksfirstsoyou'llfeelarealsenseof62achieve.Leavingthelessimportantthingsuntiltomorrow63beoftenacceptable.Mostofusaremorefocused64ourtasksinthemorningthanwearelaterintheday.Sogetanearlystartandtrytobeasproductive65possiblebeforelunch.Thiswillgiveyoutheconfidenceyouneedtogetyouthroughtheafternoonandgohomefeelingaccomplished.Recent66studyshowthatwearefarmoreproductiveatworkifwetakeshortbreaks67regular.Giveyourbodyandbrainarestbysteppingoutsidefor68whileexercisingordoingsomethingyouenjoy.Ifyoufindsomethingyoulovedoingoutsideoftheofficeyou'llbelesslikely69bringyourworkhome.Itcouldbeanything﹣gardeningcookingmusicsports﹣butwhateveritis70makesureit'sarelieffromdailystressratherthananotherthingtoworryabout.
InaclassthispastDecemberafterIwrotesomedirectionsontheboardforstudentsabouttheirfinalexaminationoneyoungwomanquicklytookapictureoftheboardusinghersmartphone.WhenIlookedinherdirectionsheapologized'Sorry.Wasitwrongtotakeapicture?''Ican'treadmyownhandwriting'theyoungwomanexplained.'It'sbestifItakeapictureofyourwritingsoIcanunderstandthenotes.'Thatremarkstartedaclass﹣wideconversationabouttakingapictureinsteadoftakingnotes.Forthoseinthephoto﹣takingcampmotivationsextendedbeyondtheirinabilitytocomprehendtheirownhandwriting.Sometookpicturesofnotesbecausetheyknewtheirphonewasasafeplacetostorematerial.Theymightlosepapertheyreasonedbuttheywouldn'tlosetheirphones.SometookphotosbecausetheywantedtorecordexactlythemannerinwhichIhadnotedinformationontheboard.Otherstoldmethatduringclasstheylikedtobeabletolistentothediscussionattentively.Yettheuseofcamerasasnotetakersthoughitmaybeconvenientdoesraisesignificantquestionsfortheclassroom.Isapictureaneffectivereplacementfortheprocessofnote﹣taking?Instructorsencouragestudentstotakenotesbecausetheactofdoingsoismorethanmerelyrecordingnecessaryinformation﹣ithelpspreparethewayforunderstanding.Encouragingstudentstotakenotesmaybeanold﹣fashionedinstructionalmethodbutjustbecauseamethodhasalonghistorydoesn'tmeanit'soutofdate.Writingthingsdownengagesastudent'sbraininlisteningvisualandkinesthetic触觉的learning﹣aviewsupportedbyalongstandingresearch.Theactofwritingdowninformationenablesapersontobegincommittingittomemoryandtoprocessandcombineitestablishingthebuildingblocksoflearningnewconcepts.Takingapicturedoesindeedrecordtheinformationbutitdeletessomeofthenecessarymentalengagementthattakingnotesemploys.Socanthetwobeequallyeffective?1Thewomanapologizedintheclassbecauseshe.A.hadthebadhandwritingB.missedtheteachers'directionsC.tookapictureoftheboardD.disturbedotherstudents'learning2Accordingtothepassagetakingnotesbyhand.A.requiresstudentstothinkindependentlyB.helpsstudentsactivelyparticipateinlearningC.provestobeanoldanduselesslearningmethodD.seemsunsuitableforstudentstolearnnewideas3Whatisthemainideaofthispassage?A.Thetraditionalwayofnote﹣takingshouldbereplaced.B.Amodernwayofnote﹣takingiscatchingon.C.Note﹣takingbyhandisnotoutofdate.D.Apictureisworthathousandwords.
8分In2009theTaiwuElementarySchoolFolkSingerswereinvitedtoperforminBelgiumFranceGermanyandLuxemburg.In2011theywerevotedasoneoftheworld'stopfiveperformancegroupsbyaudiencesofJapanBroadcastingCorporation'sAmazingVoiceprogram.Thinkingbackthegroup'sfirsttourinEuropeCamakeValauleaphysicaleducationteacherandthefounderoftheTaiwuElementarySchoolFolkSingersadmittedthathefeltverynervous.Hewasworriedthattheaudiencewouldfallasleepsincemostofthe75﹣minuteperformancewasacappellathatissingingwithoutinstrumentalsound.Surprisinglytheaudiencelistenedwithfullfocusandhighspirits.Camakesaid'Theytoldmeafterwardthatthroughourperformancetheyhadavisionofourcountryourvillagewithouthavingtovisitit.Thisexperiencegreatlyincreasedourconfidence.'AccordingtoCamakeValaulesingingtraditionalballadshashelpedstudentsandtheirparentstore﹣understandtheirculture.'Itusedtobethattheonlyoneswhocouldsingthesesongsweretribaleldersagedbetween50and60.Nowwiththechildrenperformingthepiecesparentsarebeginningtoask‘Whydowenotknowhowtosingtheseballads?'Manytimesnowadaysitisthechildrenwhoteachthesongstotheirparentsputtingbackthepiecesofablurredmemory.'WinninginternationalfamehoweverwasneithertheoriginalintentionnorthemainreasonwhyCamakefoundedthegroupin2006.Themostimportantthingwastomakechildrenunderstandwhytheysingthesesongsandtopreserveandpassontheirculture.ReferringtotherelocationofTaiwuElementarySchoolandTaiwuVillagefollowingTyphoonMorakotinAugust2009Camakesaid'Wecouldnottaketheforestorourhousesinthemountainswithusbutwewereabletobringourculturealong.AslongasthechildrenarewillingtosingIwillalwaysbethereforthemsingingwiththemandleadingthemtoexperiencethemeaningoftheballads.'1WhichofthefollowingistrueaboutTaiwuElementarySchoolFolkSingers?A.Thegroupwasfirstestablishedin2009.B.ThegroupwasfoundedbyaPEteacher.C.Thesingersusuallysingpopularfolksongs.D.Thesingerslearntosingfromtheirparents.2OnhisfirsttriptoEuropewhydidCamakethinktheaudiencemightfallasleep?A.Theaverageageoftheaudiencewasbetweenfiftyandsixty.B.Mostoftheperformancewasnotaccompaniedbyanyinstrument.C.Nobodycouldunderstandthelanguageandthemeaningofthesongs.D.Theaudiencecouldnotvisualizethethemesungbytheschoolchildren.3Whatdoestheunderlinedpart'thepiecesofablurredmemory'inthethirdparagraphmostlikelyreferto?A.Thefadingmemoriesaboutoldtribalpeople.B.Thechildren'signoranceoftheirowntradition.C.Thebrokenpiecesofknowledgetaughtatschool.D.Theparents'vagueunderstandingoftheirownculture.4WhatdidCamakerealizeaftertheincidentofTyphoonMorakot?A.ThesignificanceoftherelocationofTaiwuElementarySchool.B.Theneedtorespectnaturetoavoidbeingdestroyedbyit.C.Theimportanceofpassingonthetraditionalculture.D.Theconsequenceofbuildinghousesintheforest.
30分假设你是李华你的美国笔友Lucy写E﹣mail问你高考后暑假的计划请根据以下要点写一封100词左右的e﹣mail回复他可以适当增加细节. 1.学开车 2.参加英语培训课程 3.游览北京的名胜 注意1.根据以上内容写一篇短文不要逐句翻译可适当增加细节以使行文连贯. 2.词数100词左右开头结尾已给出不计入词数. DearLucy Howtimeflies! Bestwishes! Yours LiHua
某研究小组用新颖的NaBH4/H2O2燃料电池模拟电化学降解NO3﹣下列说法不正确的是
下列物质的转化在给定条件下能实现的是
向20mL0.1mol/LNH4HSO4溶液中滴入0.1mol/LNaOH溶液至恰好反应完全下列说法正确的是
利用如图所示实验装置可以测定常温常压下气体的摩尔体积．甲同学利用如图1装置根据下列步骤完成实验 ①装配好装置作气密性检查． ②用砂纸擦去镁带表面的氧化物然后取0.108g的镁带． ③取下A瓶加料口的橡皮塞用小烧杯加入20mL水再把已称量的镁带加到A瓶的底部用橡皮塞塞紧加料口． ④用注射器从A瓶加料口处抽气使B瓶导管内外液面持平． ⑤用注射器吸取10mL3mol•L﹣1硫酸溶液用针头扎进A瓶加料口橡皮塞将硫酸注入A瓶注入后迅速拔出针头． ⑥当镁带完全反应后读取C瓶中液体的体积记录数据． ⑦用注射器从A瓶加料口处抽出8.0mL气体使B瓶中导管内外液面持平． ⑧读出C瓶中液体体积是115.0mL．完成下列填空 1常温常压下的压强为温度为． 2在常温常压下气体摩尔体积理论值约为24.5L/mol甲同学测出此条件下lmol气体的体积为计算此次实验的相对误差为%＜保留2位有效数字．相对误差指的是测量所造成的绝对误差与被测量〔约定〕真值之比．乘100%所得的数值以百分数表示．引起该误差的可能原因． a．镁带中含铝b．没有除去镁带表面的氧化物c．反应放热d．所用硫酸的量不足 3丙同学提出可用如图2装置完成该实验．该装置气密性的检查方法是． 4与原方案装置相比丙同学使用的装置实验精度更高．请说明理由回答两条．
FiveyearsagowhenItaughtartataschoolinSeattleIusedTinkertoysasatestatthebeginningofatermtofindoutsomethingaboutmystudents.IputasmallsetofTinkertoysinfrontofeachstudentandsaid'MakesomethingoutoftheTinkertoys.Youhave45minutestoday﹣and45minuteseachdayfortherestoftheweek.'Afewstudentshesitatedtostart.Theywaitedtoseetherestoftheclasswoulddo.Severalotherscheckedtheinstructionsandmadesomethingaccordingtooneofthemodelplansprovided.Anothergroupbuiltsomethingoutoftheirownimaginations.OnceIhadaboywhoworkedexperimentallywithTinkertoysinhisfreetime.Hisconstructionsfilledashelfintheartclassroomandagoodpartofhisbedroomathome.Iwasdelightedatthepresenceofsuchastudent.Herewasanexceptionallycreativemindatwork.HispresencemeantthatIhadanunexpectedteachingassistantinclasswhosecreativitywouldinfect感染otherstudents.Encouragingthiskindofthinkinghasadownside.Irantheriskoflosingthosestudentswhohadadifferentstyleofthinking.Withoutfailonewoulddeclare'ButI'mjustnotcreative.''Doyoudreamatnightwhenyou'reasleep?''Ohsure.''Sotellmeoneofyourmostinterestingdreams.'Thestudentwouldtellsomethingwildlyimaginative.Flyingintheskyorinatimemachineorgrowingthreeheads.'That'sprettycreative.Whodoesthatforyou?''Nobody.Idoit.''Really﹣atnightwhenyou'reasleep?''Sure.''Trydoingitinthedaytimeinclassokay?'25.TheteacherusedTinkertoysinclassinorderto?A.knowmoreaboutthestudentsB.makethelessonsmoreexcitingC.raisethestudents'interestinartD.teachthestudentsabouttoydesign26.WhatdoweknowabouttheboymentionedinParagraph3?A.Helikedtohelphisteacher.B.Hepreferredtostudyalone.C.Hewasactiveinclass.D.Hewasimaginative.27.Whatdoestheunderlinedword'downside'inParagraph4probablymean?A.Mistake.B.Drawback.C.Difficulty.D.Burden.28.Whydidtheteacheraskthestudentstotalkabouttheirdreams?A.Tohelpthemtoseetheircreativity.B.Tofindoutabouttheirsleepinghabits.C.Tohelpthemtoimprovetheirmemory.D.Tofindoutabouttheirwaysofthinking.
实验室用氧化锌矿粉主要含ZnOFeCO3CuO等制备碱式碳酸锌[Zn2OH2CO3]并将其用于合成氨工艺脱硫研究． 1“酸浸”时保持H2SO4过量的目的是． 2已知Mn2+开始沉淀的pH＝8.1． ①写出加入KMnO4溶液除铁的离子方程式． ②流程中调节pH＝5.4所加试剂X为填化学式试剂XKMnO4溶液加入顺序能否互换请判断并说明理由． 3上述流程中的“滤液”可以用作化肥该滤液的主要成分为填化学式． 4合成氨原料气脱硫原理如图碱式碳酸锌吸收硫化氢的化学方程式为．
下列各装置能够达到相应实验目的是
某药物中间体X其结构如图所示．下列说法正确的是
10分Whetheryou'reachildteenageryoungadultoraremiddle﹣agedrespectforyourparentsisanimportantvalue.Yourparentsarethepeoplewhoraisedyoudevotingtimeenergyandmoneytoyourdevelopment.1Nomatteryouragethereare5waystoshowrespect.●Respecttheirbelongings.Oneimportantwaytoshowrespectistoshowregardforthethingsimportanttoyourparents.Foryoungerchildrenthismaymeannottouchingjewelryorothervaluablethings.Forgrownchildrenrespectmaymeanreturningaborrowedtoolingoodconditionandontime.Lackofrespectforaparent'sbelongingsisaviolationofpersonalboundaries.2Andneverborrowthingswithoutaskingfirst.●Punctuality.3Thereforealwaysbeontime.Forteenagersshowingupontimemeanscominghomebycurfew宵禁.Adultchildrenshouldshowupontimeforfamilydinnersoreventsortopickaparentupforamedicalappointment.Callifyou'regoingtobelatebecauseparentsworryaboutchildrennomattertheirage.●4Rememberingbirthdaysanniversariesandotherspecialdaysisasignthatyouhonoryourparents.Makeplanstotakethemtolunchordinnerorbakeacakeorcookies.Mostparentsdon'texpectexpensivegiftsbutahandmadegiftisalwaysappreciated.Aphonecallfromagrownchildwholivestoofarforavisitisawelcomesignofrespect.●Bekind.Kindwordsandaffectionaresimplewaystoshowrespect.Tellyourparentsyoulovethem.Listenandallowyourparentstospeakwithoutinterruption.Showasincereinterestinwhatyourparentshavetosay.Bepatientwithyourparentsanddon'trushthem.Nevertalkbackorberudeordisrespectful.Acknowledgeyourparents'achievements.5A.Beagoodlistener.B.Celebratewiththem.C.Latenessindicatesalackofrespect.D.Treatyourparentsthewayyouwouldliketobetreated.E.Andtheyloveyouunconditionallythroughoutyourlife.F.Beingrespectfulhelpsbuildpositiverelationshipswithothers.G.Don'ttakeadvantageofyourparents'kindnessandgenerosity.
钴及其化合物广泛应用于磁性材料电池材料及超硬材料等领域． 1CoxNi1﹣xFe2O4其中CoNi均为+2可用作H2O2分解的催化剂具有较高的活性． ①该催化剂中铁元素的化合价为． ②图1表示两种不同方法制得的催化剂CoxNi1﹣xFe2O4在10℃时催化分解6%的H2O2溶液的相对初始速率随x变化曲线．由图中信息可知法制取得到的催化剂活性更高Co2+Ni2+两种离子中催化效果更好的是． 2草酸钴是制备钴的氧化物的重要原料．下图2为二水合草酸钴CoC2O4•2H2O在空气中受热的质量变化曲线曲线中300℃及以上所得固体均为钴氧化物． ①通过计算确定C点剩余固体的化学成分为填化学式．试写出B点对应的物质与O2在225℃～300℃发生反应的化学方程式． ②取一定质量的二水合草酸钴分解后的钴氧化物其中Co的化合价为+2+3用480mL5mol/L盐酸恰好完全溶解固体得到CoCl2溶液和4.48L标准状况黄绿色气体．试确定该钴氧化物中CoO的物质的量之比．
Readingcanbeasocialactivity.Thinkofthepeoplewhobelongtobookgroups.Theychoosebookstoreadandthenmeettodiscussthem.NowthewebsiteBookCrossing.comBookCrossing.comturnsthepageonthetraditionalideaofabookgroup.Membersgoonthesiteandregisterthebookstheyownandwouldliketoshare.BookCrossingprovidesanidentificationnumbertostickinsidethebook.Thenthepersonleavesitinapublicplacehopingthatthebookwillhaveanadventuretravelingfarandwidewitheachnewreaderwhofindsit.BrucePedersonthemanagingdirectorofBookCrossingsays'Thetwothingsthatchangeyourlifearethepeopleyoumeetandbooksyouread.BookCrossingcombinesboth.'Membersleavebooksonparkbenchesandbusesintrainstationsandcoffeeshops.Whoeverfindstheirbookwillgotothesiteandrecordwheretheyfoundit.Peoplewhofindabookcanalsoleaveajournalentrydescribingwhattheythoughtofit.E﹣mailsarethensenttotheBookCrossingtokeepthemupdatedaboutwheretheirbookshavebeenfound.Brucepetersonsaystheideaisforpeoplenottobeselfishbykeepingabooktogatherdustonashelfathome.BookCrossingispartofatrendamongpeoplewhowanttogetbacktothe'real'andnotthevirtual虚拟.Thesitenowhasmorethanonemillionmembersinmorethanonehundredthirty﹣fivecountries.29.Whydoestheauthormentionbookgroupsinthefirstparagraph?A.Toexplainwhattheyare.B.TointroduceBookCrossing.C.Tostresstheimportanceofreading.D.Toencouragereaderstosharetheirideas.30.Whatdoestheunderlinedword'it'inParagraph2referto?A.Thebook.B.Anadventure.C.Apublicplace.D.Theidentificationnumber.31.WhatwillaBookCrosserdowithabookafterreadingit?A.Meetotherreaderstodiscussit.B.Keepitsafeinhisbookcase.C.Passitontoanotherreader.D.Mailitbacktoitsowner.32.Whatisthebesttitleforthetext?A.OnlineReadingAVirtualTourB.ElectronicBooksAnewTrendC.ABookGroupBringsTraditionBackD.AWebsiteLinksPeoplethroughBooks.
Agardenthat'sjustrightforyouHaveyouevervisitedagardenthatseemedjustrightforyouwheretheatmosphereofthegardenappearedtototalmorethanthesum总和ofitsparts?36.Butitdoesn'thappenbyaccident.Itstartswithlookinginsideyourselfandunderstandingwhoyouarewithrespecttothenaturalworldandhowyouapproachthegardeningprocess.●37Somepeoplemaythinkthatagardenisnomorethanplantsflowerspatternsandmassesofcolor.Othersareconcernedaboutusinggardeningmethodsthatrequirelesswaterandfewerfertilizers肥料.38.Howeverthereareanumberofotherreasonsthatmightexplainwhyyouwanttogarden.Oneofthemcomesfromourearliestyears.●Recall回忆yourchildhoodmemoriesOurmodelofwhatagardenshouldbeoftengoesbacktochildhood.Grandma'srosegardenandDad'svegetablegardenmightbegoodorbadbutthat'snotwhat'simportant.39﹣﹣howbeinginthosegardensmadeusfeel.Ifyou'dliketobuildapowerfulbondwithyourgardenstartbytakingsometimetorecallthegardensofyouryouth.40thengooutsideandworkoutaplantotranslateyourchildhoodmemoriesintoyourgrown﹣upgarden.Havefun.A.KnowwhyyougardenB.FindagoodplaceforyourowngardenC.It'sourexperienceofthegardenthatmattersD.It'sdelightfultoseesomanybeautifulflowersE.StillothersmaysimplyenjoybeingoutdoorsandclosetoplantsF.YoucanproducethatkindofmagicalqualityinyourowngardentooG.Foreachofthosegardenswriterdownthestrongestmemoryyouhave.
Lifeislikeawindingpathsurroundedbyflowersbutterfliesanddeliciousfruits______manyofusspendmuchtimelookingforhappinessaroundthenextcorner A.therefore B.though C.moreover D.otherwise
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