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已知函数f(x)=(3x﹣1)a﹣2x+b (1)若f()=,且a>0,b>0,求ab的最大值; (2)当x∈[0,1]时,f(x)≤1恒成立,且2a+3b≥3,求z=的取值范围.
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高三上学期数学《》真题及答案
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已知函数fx=2x3﹣3x若过点P.1t存在3条直线与曲线y=fx相切则t的取值范围为
(﹣∞,﹣3)
(﹣3,﹣1)
(﹣1,+∞)
(0,1)
函数fx=ax3+3x2+3xa≠0.Ⅰ讨论fx的单调性Ⅱ若fx在区间12是增函数求a的取值范围.
已知函数fx=丨x2+3x丨x∈R若方程fx-a丨x-1丨=0恰有4个互异的实数根则实数a的取值范
已知函数fx=3x2+2x+1若成立则a=___________
已知函数fx=x3+ax2﹣3xa∈R..1若函数fx在区间[1+∞上是增函数求实数a的取值范围2若
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设函数fx=x3+3x2+1.已知a≠0且fx–fa=x–bx–a2x∈R则实数a=b=.
已知函数fx=lnx+x2.1若函数gx=fx-ax在定义域内为增函数求实数a的取值范围2在1的条件
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已知函数fx=ax3-3x2+1若fx存在唯一的零点x0且x0>0则a的取值范围为
(2,+∞)
(-∞,-2)
(1,+∞)
(-∞,-1)
已知函数fx=ax3﹣3x2+1若f﹣afaf3a成公差不为0的等差数列则过坐标原点作曲线y=fx的
0条
1条
2条
3条
给出下列四个命题其中正确命题的序号是①已知fx=x2+bx+c是偶函数则b=0②若函数fx的值域为[
①②⑤
①②④⑤
①②③⑤
①③④⑤
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已知函数fx=ax3-3x2+1若fx存在唯一的零点x0且x0>0则a的取值范围是
(2,+∞)
(-∞,-2)
(1,+∞)
(-∞,-1)
对于三次函数fx=ax3+bx2+cx+da≠0定义f″x是函数y=fx的导函数y=f'x的导函数.
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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.
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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
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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
可持续发展需要注意“环境保护”和“节约能源”. ①近年来一些国家为治理“白色污染”提出3R运动即要求做到废弃塑料的减量化再利用和. ②某污水处理厂处理含酸性物质泥沙等的污水时常先加入混凝剂经曝气沉砂后再加入熟石灰处理加入熟石灰的目的是. ③汽车尾气的大量排放会引起环境污染写出NO和CO在催化剂作用下转化为无污染的两种气体的化学方程式.
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.
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.
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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.
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
“矿石熊猫”由我国地质学家首次发现它由前20号元素中的6种组成其化学式为X3Y2ZWR43T2其中XYZ为金属元素Z的最外层电子数与次外层相等XZ位于同族YZRT位于同周期R最外层电子数是次外层的3倍T无正价X与R原子序数之和是W的2倍.下列说法错误的是
菠菜营养丰富素有“蔬菜之王”的美称.民间流传菠菜豆腐同食易得结石.某化学兴趣小组对“菠菜豆腐是否不能同食”等问题进行探究. 已知菠菜含有丰富的铁草酸盐碳酸盐等豆腐中含有丰富的蛋白质及钙盐等.人体结石的主要成分草酸钙CaC2O4.醋酸不与草酸钙反应但能与碳酸钙反应生成可溶性盐等. [探究一]菠菜中部分成分分析 1步骤②中的实验室操作中需要的玻璃仪器有. 2白色沉淀B的化学式可能为. [探究二]某草酸钙晶体CaC2O4•xH2O热分解研究 按如图装置将某草酸钙晶体样品高温加热使其完全分解对所得气体产物进行探究假设装置中各试剂均足量. 3某研究所利用SDTQ600热分析仪对草酸钙晶体CaC2O4•xH2O进行热分解得相关数据绘制成固体质量﹣分解温度的关系如图. ①800℃以上时固体成分的化学式为. ②写出固体质量由12.8g变为10.0g时的反应方程式. ③计算草酸钙晶体的x写出计算过程.根据图象可知0~200℃是晶体失去结晶水的过程14.6克CaC2O4•xH2O失去水后生成12.8克CaC2O4则 CaC2O4•xH2O~CaC2O4 128+18x128 14.612.8 = 解得x=1.
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
某溶液除水电离出的HO﹣H+之外仅含Fe2+Na+Al3+Ba2+SO42﹣NO3﹣Cl﹣中的4种这4种离子的物质的量均为0.1mol.若向该溶液中加入少量稀硫酸无沉淀生成但有气泡产生.下列说法错误的是
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.
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.
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