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下列实验现象描述正确的是（ ）
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观察和实验是学习化学的重要方式下列实验现象描述正确的是
下列对实验现象描述不正确的是
描述下列实验现象其中正确的是
化学是一门以实验产基础的学科化学实验时要注意观察实验现象下列实验现象描述不正确的是
观察和实验是学习化学的重要方式．下列对有关实验现象的描述中正确的是
正确描述实验现象是进行化学实验的一项基本技能．下列实验现象描述正确的是
铜绿受热分解，变成红色固体
木炭在氧气中燃烧，发出白光，放出二氧化碳
细铁丝在氧气中剧烈燃烧，火星四射，生成黑色固体
电解水时，收集到的氢气和氧气的气体质量比为1：2
下列对有关实验现象的描述正确的是
下列化学实验现象描述正确的是
下列有关实验现象的描述正确的是
红磷燃烧产生白雾
硝酸铵溶于水温度升高
碘与淀粉作用呈蓝色
铁与稀硫酸反应溶液为棕黄色
实验是化学研究的基础对下列实验的现象描述不正确的是
实验①溶液不褪色
实验②溶液褪色
装置③用于石油的分馏
实验④饱和碳酸钠溶液上方出现油状液体
下列对实验现象的描述正确的是
实验是化学研究的基础下列有关实验装置或现象描述正确的是
图2溶液褪色，加热后不恢复
图3烧瓶中形成喷泉
图4制取少量氨气
图5石油分馏
下列关于实验现象的描述不正确的是
科学实验是人类获取科学知识验证科学理论的重要手段其中对实验现象的正确描述很重要以下实验现象描述正确的
红磷在空气中燃烧，产生大量白雾
细铁丝在氧气中燃烧，火星四射，生成白色固体
氢氧化钠溶液与硫酸铜溶液混合产生蓝色沉淀
硫在空气中燃烧发出蓝紫色的火焰
下列对有关实验现象的描述正确的是
下列有关实验现象的描述不正确的是
正确观察描述实验现象是同学们必备的实验技能右图所示的两个实验现象都有错误请加以改正实验⑴将燃着蜡烛迅
下列实验现象描述正确的是
下列实验现象描述正确的是
下列关于实验现象的描述中正确的是
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下列说法不正确的是
随着科技的发展家用电器种类越来越多家庭用电安全也越来越受到人们的重视从安全用电角度下列说法中正确的是
小李同学在探究电流与电压关系的实验请完成下列各题 1按照图甲所示的电路图请用笔画线代替导线完成图乙所示的实物图的连接电表均选小量程． 2连接电路时开关应处于状态． 3在做探究电流与电压关系的实验时要求保持电阻阻值不变通过改变电阻两端的观察电流大小的变化． 4如图丙所示是他在实验中的第三次测量结果其中电压U为V电流I为A． 实验记录定值电阻R＝6Ω 5分析实验数据可以得出结论在一定时通过导体的电流与导体两端的电压成．
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8分AboutthreedecadesagoChinawasknownastheBicycleKingdom.Butlateronbikeswerereplacedbytheirfuel﹣poweredcompetitors. ButrecentmonthshaveseenarevivalofthehumblebikeacrossChinawithanincreasingnumberofpeoplechoosingcyclinginsteadofdrivingtoschoolstoworkplacesortodosightseeing.Theintroductionofbike﹣sharingschemespioneeredbystart﹣upslikeOfoandMobikehasbroughtthetrendtoanewlevel. Peoplecanunlockthesharedbikesbysimplyusingtheirsmartphone.ThebikesareequippedwithGPSandcanbeleftanywhereinpublicforthenextuser.They'repopularamongmanyChinesepeopleastheyprovideaneffectivesolutiontothelastmileproblemwhichreferstothefinallegofaperson'sjourney. Inplaceswherethesubwaydoesn'textendwhereit'sdifficulttochangefromonekindoftransporttoanotherit'ssoeasytogetwhereyouwanttogowithMobikeHuHong29toldAFP.ShepedalstoherShanghaireal﹣estatejob. Howevertheschemeshavealsoledtoproblemssuchasillegalparkingvandalismandtheft.LastmonthtwonursesinBeijingwereplacedunderadministrativepunishmentforfivedaysforputtinglocksontwosharedbikes.AndinDecemberamanwhostoleasharedbikewassentencedtoa3﹣monthdetentionwitha3﹣monthprobationandfined1000yuanbytheShanghaiMinhangPeople'sCourt. Bike﹣sharingisagreenermethodoftransportationandprovidesauser﹣friendlyexperiencesaidLiuXiaomingvice﹣ministeroftransport.Butit'sacombinationofonlineandofflinebusiness.Operatorsareusuallystronginonlineservicesbutlackofflinebusinessexperiencewhichcausesproblems.Todealwiththeseproblemsthecompanycameupwiththeideaofencouragingpeopletoreturnthebikestostationsbyrewardingfreetimefortheirnextrides. 32.Whohasbroughttherevivalofbiketoanewlevel? A.Thelocalgovernment B.Thebusinessman C.Thestudentsandworkers D.Thepioneeredstart﹣ups 33.Whichofthefollowingdoesn'tbelongtothelastmileproblem? A.Missingthebusinessplanefortrafficjam. B.Togettosomewherethesubwaydoesn'treach. C.Havingtroublesinchangingfrombustotaxi. D.Havingnofinallegofaperson'stravel. 34.Whatreasoncausesmanyproblemsinbike﹣sharing? A.Somepeoplemakedamagetothebikesonpurpose. B.Operatorslackofflinebusinessexperience. C.Thebike﹣sharingbusinessistoocomplicatedtorun. D.Therearenorelativelawsonthisbusiness. 35.What'sthebesttitleofthispassage? A.BicycleKingdombecamefamousagain. B.Anewwayoftransportation. C.Ridingbikesforfree. D.Bikespedalingbackintostyles.
如图是一个多面体的表面展开图如果面F在前面从左面看是面B那么从上面看是面．填字母
如图所示的电路中R1R2为定值电阻电源电压不变闭合开关S1S2两表均有示数若闭合开关S1断开开关S2则
15分Dr.GeYunhashelpedmanykidswhowerebornwithdefects缺陷61includeme.ShedidmyfirsttwooperationswhenIwasababywhichwerethemostimportantand62effect. Idon'trememberthefirsttwooperationsverywell.63Idorecallthethird.Dr.GeYunwaskindandeasedmeintotheprocess.Shetriedeverythingshecould64makesurethatIwasokay.I65recentsawapictureofmebeforemyoperationandIknewwhatabigjobshedid. Dr.GeYunoperates66peoplewithalltypesofbirthdefects.Shealsogoestoothercountries67peoplecannotaffordthetreatmentandhelpsthemforfree.Manypeoplebenefitfromhernewways68inventtofixbirthdefectsoftheheadandface.She69winmanyawardssofar. ThoughIwasjustoneofthepatientstohertomeshewas70muchthanjustmydoctor.Shewasandismyheroandshereturnedthesmiletome.
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|﹣3|的相反数是．
下列用电器利用电流的热效应工作的是
解不等式并把它的解集在数轴上表示出来． ﹣＞﹣3
8分AreportbytheUS'OpenSyllabusProjectfoundthatthemostreadbooksamongUScollegestudentsinthepastyearwerethelikesofTheRepublicbyancientGreekphilosopherPlatoandTheClashofCivilizationsbyUSpoliticalscientistSamuelHuntington.AndaccordingtoreportsreleasedbyChinesecollegelibrariesthemostpopularbooksamongChinesestudentsarenovelslikeJourneyUndertheMidnightSunbyJapanesewriterKeigoHigashinoandDemi﹣GodsandSemi﹣Devils天龙八部byChineseauthorLouisCha. ThisisconsideredbymanytobeoneofthereasonswhyChinesestudentsaresometimesnotasgoodatcriticalthinkingorobservingglobalperspectivesasUSstudents﹣theyreadtoomanybestsellernovels. ByreadingtextsinsocialstudiesscienceandotherdisciplinesstudentsbuildafoundationofknowledgeinthesefieldsthatwillalsogivethemthebackgroundtobebetterreadersinallareasRobertPondisciovicepresidentoftheCoreKnowledgeFoundationintheUStoldTheWashingtonPost. AccordingtoChinaYouthDailythereareusuallyfivestageswhenitcomestoreadingwithpopularnovelsatthebottom.Moreadvancedreadersnormallygoontoreadclassicfictionalliteraturehistoryandphilosophyorbookswithcriticalideas.Thefifthstageinvolvesstudentsmakingtheirownreadinglistsbasedontheideological意识形态的systemstheyhavebuiltthroughouttheyears. Wespendhoursdaysorevenweeksonabooksoit'sonlynaturalthatwewanttolearnsomethingusefulinreturnforourefforts.Manyseereadingasaninvestmentinthemselves. Butthispracticalviewofliteratureandthethoughtthathistoryandphilosophybooksaresuperiortonovelsisnotagreedbyeveryone.Afterallwhattheyofferaretwodifferentkindsofsatisfaction.Whiletheformerprovidesknowledgethelatterbringssentimental情感的experiences.FictionandpoetryaremedicinesUKwriterJeanetteWintersononcewrote.Whattheyhealistherupture裂痕realitymakesontheimagination. 24.Thepurposeofparagraphoneisto. A.comparethepopularbooksbetweentheUSandChinesestudents. B.introducethedifferentdiscoveriesfromChinaandtheUS. C.analyzetheculturaldifferencesofthetwocountries. D.statewhyChinesestudentsaresometimesnotgoodatcriticalthinking 25.Toknowsomethingineachareastudentsshouldread. A.famousnovelswhichhaswonmanyprizes B.textsinsocialstudiesandotherdisciplines C.modernmagazineswhichhavegainedgreatpopularity D.sciencefictionsinvolvingknowledgeinmanyareas 26.AccordingtoChinaYouthDailywhichisthehigheststagewhilereading? A.Booksbasedonthereaders'thought. B.Classicfictionalliterature. C.Bookswithcriticalideas. D.Popularnovels. 27.Whatcanweinferfromthelasttwoparagraphs? A.Historybooksaresuperiortonovels. B.JeanetteWintersonthoughtfictionandpoetryarealsouseful. C.Philosophybookshelpthereadersgetemotionalexperience. D.Thewriterpreferstoreadthehistoricalandscientificbooks.
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如图甲所示是小明在做“用伏安法测量某定值电阻R的阻值”的实验电路图 1实验前滑动变阻器的滑片应置于填“最左”或“最右”端其目的是为了． 2闭合开关移动滑动变阻器滑片P发现电压表始终无示数电流表有示数其原因可能是填字母 A滑动变阻器断路BR断路CR短路 3排除故障后当电压表的示数如图乙所示时电流表的示数如图丙所示则定值电阻的阻值是Ω． 4通常情况下要进行多次测量并取平均值其目的是为了．
10分TipsforStayingSharpIt'snotabnormaltofeeloutofitfromtimetotimeorperhapsyou'refeelingabitsluggish迟钝的whenitcomestorememberingthings.Ifyou'reworriedaboutyourforgetfulnesstryoutthesefivetipstostaysharp.36You'veprobablyheardthetermyouarewhatyoueat.Ifyoudecidetoeatsugaryfoodsthatareheavywithfatsthenexpecttofeellazyandhavenoenergy.Butifyoudecidetoeatfruitsvegetablesandmakeotherhealthyeatingdecisionsyou'11findthatyou'refullofenergy.NeverstoplearningChallengeyourselfconstantly﹣whetheritispuzzlesreadingcookingorothertasksthatwillkeepyourmindworking.Ifyourmindisalwayslearningnewthingsandactiveyou'11realizethatit'smucheasierforyoutolearnnewthingsandtofunction.37StayfitBeingingoodhealthandstayinginshapeisabigpartofstayingsharp.38Ifyouchoosetobelazythenyourbodyisnotgoingtogiveyoutheenergythatrequiresrememberingthingsandcompletingtasks.Howeverifyouputforththeeffortintobeinghealthythenyourbodywillexpel释放theenergyyouneedtoachieveyourgoals.EnsureenoughsleepBesuretogetthenecessaryamountofsleepthatyourbodyneedstofunctiononadailybasis.39Italsohelpsyourbodybuildupanenergyreservesoyoucanimproveyourabilitytofocusandavoiddistractions.Socializemore40Socialinteractionwillhelpyoudevelopmultitaskingproblemsolvingandotherskillsthatarenecessaryinlifetokeepyourmindsharp.A.Feedyourbrain.B.Avoideatingtoomuch.C.Yourbodywillonlygiveyouwhatyouputintoit.D.Lackofsleepcontributestotirednessandslowreaction.E.Conversationsrequireindividualstostayawareandactive.F.Accordingtostudiessleephelpsstrengthenandrecoveryourmemories.G.Rememberyourbrainisamuscleandifyouwanttogetthemostoutofityoumustuseit.
已知抛物线y＝﹣x2+bx+c的对称轴为直线x＝1其图象与x轴相交于AB两点与y轴相交于点C03． 1求bc的值 2直线1与x轴相交于点P． ①如图1若l∥y轴且与线段AC及抛物线分别相交于点EF点C关于直线x＝1的对称点为点D求四边形CEDF面积的最大值 ②如图2若直线1与线段BC相交于点Q当△PCQ∽△CAP时求直线1的表达式．
小明家电能表上个月底的示数为这个月底的示数如图所示可知他家本月电能表的表盘转了圈．他家最多能接入总功率为W的用电器．
25分假定你是李华学校将于5月底开展英语阅读周活动请给你的英国笔友Peter写信向他说明该活动的目的和意义并请他推荐适合高中生阅读的英文书籍. 注意: 1.词数100左右; 2.可适当增加细节以使行文连贯. .
8分Giantkitescouldsupplygreenenergywithouttheneedfortaxpayer﹣fundedsubsidies津贴withinyears.KitePowerSolutionsexpectstoopentheU.K.'sfirstkitepowerplantthisyearinScotland.Ithopestolaunchthetechnologyonshoreandatseabuildingsystemswiththecapacitytoproducehundredsofmegawattsofpowerwithinthedecade.Thecompanybelievesthetechnologycouldreducethecostofwindenergy.Anditpredictedthatkitepowerwouldcostsolittlethatdevelopingcountrieswouldbemorelikelytouseittofreethemselvesoffpollutingcarbon﹣heavyenergysources.AspokesmanAinsworthforKitePowerSolutionssaidthetechnologycoulddecreasethecostofoffshorewindenergymeetingtheneedforgovernments'effortstoreducecarbonemissions排放.Hesaidthetechnologywaseasytofixandmaintainmeaningitcouldbeusedindeepwateronfloatingstructuresfarfromshore.Ifwedothatitopensupaglobaldeepwateroffshorewindmarkethesaid.ThetechnologycouldcontrolrisingCO2emissionsinthedevelopingworldwheretheneedtosavemoneyforcespeopletoadopttopollutingtechnologiessuchasdiesel.ThecompanyhastestedthetechnologyonasmallscaleinEssexandwillmoveitsheadquarterstoGlasgowtopreparefornextyear'slaunch.Ithaswonplanningpermissionfora500KWdemonstrationsystem.TheU.K.'sgreenenergytradebodyRenewableU.K.welcomedthetechnologybutwarneditwasnotasilverbullet.ThedeputychiefexecutiveMarSmithsaid:Thisisanambitiousprojecttodevelopwindpoweratextraordinaryheightsanditshowsthelevelofnewideaswithintherenewableindustry.Kitepowerisatanearlystageofdevelopmentanditwilltaketimetoseehowthetechnologyprogresses.Anywaywewillneedawiderangeofenergysourcesinthefuturetomeetourneedsinanenvironmentallyfriendlyway.28.Whatisthebiggestadvantageofkitepower?A.Itslowcost.B.Itswideuse.C.Itsgreatflexibility.D.Itshighquality.29.IntheeyesofAinsworthkitepowercan.A.getridofairpollutionB.beconvenienttouseC.helpexploretheoceanD.dealwithwatershortage30.Whatdoestheunderlinedphraseasilverbulletmean?A.ascientificideaB.apracticalwayC.aquicksolutionD.asuitablechoice31.Whatistheauthor'spurposeinwritingthepassage?A.Toargueforcleanerenergies.B.Tointroduceanewwaytogetenergy.C.Toadvertiseagreatenergycompany.D.Tocomparedifferentenergyresources.
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