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如图所示，一玻璃球体的半径为R，O为球心，AB为直径．来自B点的光线BM在M点射出，出射光线平行于AB，另一光线BN恰好在N点发生全反射．已知∠ABM＝30°，求 ①玻璃的折射率． ②球心O到B...
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高三下学期物理《》真题及答案
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如图所示MN为竖直放置的光屏光屏的左侧有半径为R.相对空气折射率为的透明玻璃半球体O.为球心轴线OA
如图所示是一玻璃球体其半径为RO为球心AB为直径M点是玻璃球的最高点来自B点的光线BD在D点射出出射
如图所示一玻璃球体半径为R.O.为球心AD为水平直径来自A.点的单色光从B.点射出出射光平行于AD已
2017年·葫芦岛一模如图所示一玻璃球体的半径为RO为球心AB为直径．来自B点的光线BM在M点射出出
如图为一玻璃球过球心的横截面玻璃球的半径为RO为球心AB为直径来自B点的光线BM在M点射出出射光线
如图一玻璃工件的上半部是半径为R.的半球体O.点为球心下半部是半径为R.高位2R.的圆柱体圆柱体底面
2015年·丹东一模如图所示一玻璃球体的半径为RO为球心AB为直径在球的左侧有一竖直接收屏在A点与玻
如图所示真空中有一个半径为R.折射率为n=的透明玻璃球.一束光沿与直径成θ0=45°角的方向从P.点
如图所示一玻璃球体的半径为RO为球心MN为直径OA与OM夹角为30°一细束光线沿与OA夹角为60°
如图一玻璃工件的上半部是半径为R.的半球体O.点为球心下半部是半径为R.高位2R.的圆柱体圆柱体底面
如图所示一玻璃球体的半径为RO为球心AB为直径在球的左侧有一竖直接收屏在A点与玻璃球相切．自B点发
如图所示玻璃球的半径为R折射率n=今有一束平行光沿直径AB方向照射在玻璃球上试求离AB多远的入射光线
如图所示一玻璃球体的半径为RO为球心MN为直径OA与OM夹角为30°一细束光线沿与OA夹角为60°
如图所示一玻璃球体的半径为RO为球心MN为直径OA与OM夹角为30°一细束光线沿与OA夹角为60°
一半径为R.的1/4球体放置在水平面上球体由折射率为的透明材料制成现有一束位于过球心O.的竖直平面内
如图所示有一个均匀带电球体球心为O.半径为R.电荷体密度为ρ球内有一个球形的空腔半径为R.’OO’的
如图所示一个半径为R的绝缘球壳上均匀带有+Q的电荷另一个电荷量为+q的电荷放在球心O上由于对称性点电
如图所示一玻璃球体的半径为RO为球心MN为直径从N点向玻璃球内发出两条相同的单色光线其中光线NP在
如图所示为一玻璃球的截面图其半径为R.O.为球体的球心AB为截面圆的直径在A.点放一个能发某种单色光
一半径为R.的1/4球体放置在水平面上球体由折射率为的透明材料制成现有一束位于过球心O.的竖直平面内
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下列说法中正确的是
在溶液中能大量共存的一组离子或分子是
10分英语课上老师要求同学相互修改作文.假设以下文章为你同桌所写请你对其进行修改.文章中共有10处错误每句中最多有两处.错误涉及一个单词的增加删除或修改. 增加:在缺词处加一个漏词符号∧并在此符号下面写出该加的词. 删除:把多余的词用斜线﹨划掉. 修改: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. Alicewasnotontimeforschoolinthismorning.Shelookedlittletiredwhenshemetherchemistry'steacherMissGreen.Sheapologizedforherbeinglately.MissGreenaskedheriftherewassomethingwrongwithher.Thegirlsaidthathewasallrightsoshedidn'thavemuchsleeplastnight.Shewenttoafootballgameandtooksomepictures.Aftershegothomeshewasbusydevelopedthem.Shestayeduptillmidnight.MissGreentoldhertogetmoresleepatnight.Alicepromisesnottodothatagain.ThenAliceshowedMissGreenherbeautifulpicture.
木质素是制浆造纸工业的副产物具有优良的物理化学特点若得不到充分利用变成了制浆造纸工业中的主要污染源之一不仅造成严重的环境污染而且也造成资源的重大浪费．木质素的一种单体结构简式如右图所示下列说法错误的是
30分RecentlyIpaidavisittoHarvardUniversitywheretherearetopclassscientistsandprofessorsandthebestacademicsystemintheworld. Iwasvery1whenIfirststeppedintothecampus校园.Wellit'snotevenreallyacampus.It's2likeanareainasmalltown.Harvard'smainbuildingsarefromthe18thcentury.Theylookveryoldand3.Youmight4saythey'realittleshabby破旧.Theydon'tfitthemodern5ofuniversityatall.Thebuildingsare6byflowersandtreessoIfeltasifIhadwalkedintoacastleoftheMid﹣Ages.ButwhenIlookedacrossthestreetthe7shopsandin﹣fashion时尚的studentsmademefeellikeIwasinthe21stcentury8.Itcreatesastrongcontrast对比andbringsaspecial9Ourtour10Garytookusaroundandtoldus.Youseethisgrassfieldinthecenteroftheschool?Hereiswheretheyholdtheir11ceremony仪式礼节.Theyjustsetuptentsandbenchesandhaveaverysimpleceremony.It's12!Whowouldthinkthemosttalentedstudentsjustgraduateonthegrass? I13somestudentsputablanketonthegrassandliedowntoreadabook.WhenIlistenedtothesoftsoundof14turningalongwiththesingingofthebirdsIfeltvery15.Therewasnocompetitivefeelingatall. Harvardhastheworld'sfirstcomputerinitssciencecentre16therearehundredsofhigh﹣endcomputerstoo.Itsreligionandtheliterature文学departmentsarealso17thebest.Itistheperfectmixoftraditionand18technology.ItmakesHarvardaveryattractiveplaceto19in. IhopeonedayI'll20mydreamschool﹣﹣﹣Harvard. 1.A.excited B.troubled C.shocked D.tired 2.A.more B.less C.little D.most 3.A.great B.solid C.noisy D.simple 4.A.still B.even C.ever D.yet 5.A.model B.way C.idea D.example 6.A.filled B.recovered C.surrounded D.floated 7.A.empty B.quiet C.free D.busy 8.A.once B.again C.only D.then 9.A.environment B.view C.atmosphere D.condition 10.A.guide B.partner C.visitor D.professor 11.A.celebration B.closing C.opening D.graduation 12.A.uninteresting B.unbelievable C.unbearable D.uncomfortable13.A.had B.saw C.felt D.imagined 14.A.books B.benches C.blankets D.pages 15.A.lucky B.calm C.nervous D.puzzled 16.A.but B.and C.though D.yet 17.A.among B.about C.to D.under 18.A.old B.new C.fast D.fresh 19.A.travel B.live C.study D.tour 20.A.serve B.visit C.find D.attend
在容积为2.0L的密闭容器内物质D在T℃时发生反应其反应物和生成物的物质的量随时间t的变化关系如右图据图回答下列问题 1从反应开始到第一次达到平衡时A物质的平均反应速率为mol/L•min． 2根据右图写出该反应的化学方程式该反应的平衡常数表达式为K＝． 3第5分钟时升高温度ABD的物质的量变化如右图则该反应的正反应是填“放热”或“吸热”反应反应的平衡常数填“增大”“减小”或“不变”．下同B的反应速率． 4若在第7分钟时增加D的物质的量A的物质的量变化正确的是用图中abc的编号回答
下列有机物系统命名正确的是
实验室中准备有以下主要仪器及用品大试管带导管的单孔塞药匙镊子水槽集气瓶玻璃片酒精灯铁架台如果药品选用合理用以上仪器用品能完成的实验有
两种一元碱MOH和ROH的溶液分别加水稀释溶液pH的变化如图所示下列叙述不正确的是
某反应池中发生“生物硝化过程”利用O2将NH4+氧化成NO3﹣如果不考虑过程中硝化细菌的增殖其净反应如下式所示 +++ 完成上述反应的离子方程式并配平将系数填入方框中并标出电子的转移方向和数目． 1反应中还原剂是被还原的元素是． 2将铵态氮中的lmg氮转化成硝酸根中的氮需氧气mg．精确到0.01 3取100mL完全反应以后的溶液加入19.2g铜粉及一定量的稀硫酸恰好完全反应假设还原产物全部是NO气体则原溶液中NH4+的浓度为mol/L．假设反应前后溶液的体积不变
10分 Flavoring Mostdrinksstatingthattheyarefruit﹣flavored水果味道的containnofruitatallwhilemostoftherestcontainonlyasmallquantityoffruitaccordingtoastudycarriedbytheBritishFoodCommission. Shoppersneedtocheckthelabels标签beforebuyingdrinksthoughsometimestheactualcontentcanbenon﹣existentsaidFoodCommissionspokespersonIanTokelove.Foodproductionishighlycompetitive.1Itwillincreaseprofitsandconsumerswon'talwaysrealizetheyarebeingtricked. Flavoringsarefocusedontheflavorsofnaturalfoodproductssuchasfruitsmeatsandvegetablesorcreatingflavorforfoodproductsthatdonothavethedesiredflavors.Researchersanalyzedthecontentsof28strawberry﹣flavoredproductssoldinstores.2Ofthe11productsthatdidcontainstrawberriesfiveofthemcontainedlessthanonepercentrealfruit.Inadditioneachjuiceboxcontainednearlyeightteaspoonsofsugar. 3Let'stakejamasanexample.Somestrawberry﹣flavoredjamwaslabeledascontainingnoartificialcolorsflavorsorsweetenersbutitcontainedabsolutelynostrawberriesatall. 4Consumershavetherightstoknowclearlyaboutwhattheyhavebought.UndercurrentUKlawfoodpackagesdonothavetodistinguishbetweennaturalandartificialflavoring.Describingaproductasstrawberryflavorandcoveringthesurfaceofthepacketwithpicturesofstrawberriesismisleading.5UnfortunatelyitisalsolegalandwidespreadTokelovesaid.It'stimetotakemeasurestoprotecttheconsumers'rights. A.Theproductswhichcontainrealfruitarepopularwithpeople. B.Evenproductsadvertisedasmorenaturaloftencontainednofruit. C.Theyfoundthatabout60vpercentofthemdidn'tcontainanyfruitatall. D.Ifcompaniescancuttheircostsbyusingflavoringtheyarelikelytodoso. E.Itisimportantandneessarytodemandasmallamountofflavoringintheproducts. F.Actuallytheproductcontainsjustatinypercentageofstrawberryorevennofruitatall. G.TheFoodCommissionsuggestedallflavorsusedinaproductshouldbelistedonthepackaging. 1. 2. 3. 4. 5.
有MXYZW五种原子序数依次增大的短周期元素其中MZ同主族X+与M2﹣具有相同的电子层结构原子半径Z＞WY的单质晶体熔点高硬度大是一种重要的半导体材料．下列说法正确的是
常温下浓度均为0.1mol/L的三种溶液①CH3COOH溶液②NaOH溶液③CH3COONa溶液下列说法中不正确的是忽略混合前后溶液体积变化
8分Howfarwouldyoubewillingtogotosatisfyyourneedtoknow?Farenoughtofindoutyourpossibilityofdyingfromaterribledisease?Thesedaysthat'smorethananacademicquestionasTracySmithreportsinourCoverStory. Therearenowmorethanathousandgenetic基因的testsforeverythingfrombaldnesstobreastcancerandthelistisgrowing.Questionisdoyoureallywanttoknowwhatmighteventuallykillyou?ForinstanceNobelPrize﹣winningscientistJamesWatsononeofthefirstpeopletomaptheirentiregeneticmakeupissaidtohaveaskednottobetoldifhewereatahigherriskforAlzheimer老年痴呆症. IfItellyouthatyouhaveanincreasedriskofgettingaterriblediseasethatcouldweighonyourmindandmakeyouanxiousthroughwhichyouseetherestofyourlifeasyouwaitforthatdiseasetohityou.ItcouldreallymessyouupsaidDr.RobertGreenaHarvardgeneticist. EveryacheandpainSmithsuggestedcouldbeunderstoodasthebeginningoftheend.That'sright.IfyoueverworriedyouwereatriskforAlzheimer'sdiseasetheneverytimeyoucan'tfindyourcarintheparkinglotyouthinkthediseasehasstarted. Dr.Greenhasbeenthinkingaboutthisissueforyears.HeledastudyofpeoplewhowantedtoknowiftheywereatahighergeneticriskforAlzheimer's.Itwasthoughtthatpeoplewhogotbadnewswouldforlackofabettermedicaltermfreakout.ButGreenandhisteamfoundthattherewasnosignificantdifferencebetweenhowpeoplehandledgoodnewsandpossiblytheworstnewsoftheirlives.Infactmostpeoplethinktheycanhandleit.PeoplewhoaskfortheinformationusuallycanhandletheinformationgoodorbadsaidGreen. 1.Thefirstparagraphismeantto. A.asksomequestions B.introducethetopic C.satisfyreaders'curiosity D.describeanacademicfact 2.WhichofthefollowingistrueofJamesWatson? A.Heisstronglyinfavorofthepresentgenetictests. B.HeismorelikelytosufferfromAlzheimer'sdisease. C.Hebelievesgeneticmappingcanhelpcureanydisease. D.Hedoesn'twanttoknowhischanceofgettingadisease. 3.TheunderlinedpartfreakoutinParagraph5isclosestinmeaningto. A.breakdown B.dropout C.leaveoff D.turnaway 4.ThestudyledbyDr.Greenindicatesthatpeople. A.prefertoheargoodnews B.tendtofindoutthetruth C.canacceptsomebadnews D.havetherighttobeinformed
将Fe和Fe2O3的混合物加入25mL2mol/L的HNO3溶液中反应完全后无固体剩余生成224mLNO气体标准状况再向反应后的溶液中加入1mol/L的NaOH溶液要使铁元素全部沉淀下来所加NaOH溶液的体积至少是
8分Aslifeexpectancyincreasesnowadaystheaveragepersonliveswellbeyondtheageofretirement.Asaresulttheelderlymakeupanever﹣increasingpercentageofsocietywhichmakesitmoreimportantthaneverforarealefforttobemadeinimprovingthelivesofseniorcitizens. Onewaytodealwiththesituationwouldbetoensurethattheelderlyhaveenoughmoneyonwhichtolive.Obviouslywhenapersonstopsworkingtheystillrequireasourceofincometocovertheirbasicneedssuchasfoodaccommodationandheating.Aclearsolutiontotheproblemisforthegovernmenttomakesurethatthestatepensionisadequatefortheseneeds. Stepsshouldalsobetakentoovercomethehealthproblemstheelderlyface.Thegovernmentshouldalsoprovideaccesstothebesthealthcareavailablewhichmaynecessitatepayingforresidentialhomeswheretheelderlycanhaveround﹣the﹣clocknursingorattheveryleastprovidingmedicationfreeofchargetoallpeopleoveracertainage. Thelivesofoldpeoplecouldbeimprovedifattemptsweremadetoaddresstheproblemofsocialisolation.Ifweorganisedtripsfortheelderlytocommunitycentresvisitsfromsocialworkerstheirproblemoflonelinesscanbereducedalotwhichmarksthelivesofsomanyoldpeoplelivingaloneandfarfromtheirfamilies. Onefinalsuggestionwhichwouldhelpenormouslyistochangetheattitudeofthecommunitytowardsitsoldermemberswhoarealltoooftenseenasaburdenonsocietyanddismissedashavinglittletodowithmodernlife.Weneedtobetaughtfromanearlyagetorespecttheviewsofoldpeopleandappreciatetheirbroaderexperienceoflife.Thiswouldhelpsocietyasawholeandencourageappreciationoftherolethatoldpeoplecanstillplaytoday. 1.Whatdoesthepassagemainlytalkabout? A.Alltheelderlycanenjoyfreemedication. B.Thenursescantakegoodcareoftheelderly. C.Somesuggestionswouldbemadetoimprovethelivesoftheelderly. D.Thehealthcareavailabletotheelderlyisgood. 2.TheunderlinedwordaddressinParagraph4probablymeans. A.findout B.dealwith C.putdown D.pickup 3.Whatfactorsaffectedtheoldpeople'slife? a.thestatepension b.thebasicneeds c.theattitudeofthecommunity d.theexperienceoflife e.socialisolation f.medicalcare A.abcd B.bcde C.cdef D.acef 4.Accordingtothelastsuggestiontheoldpeople. A.shouldberespectedbyallofus B.havetogathermorelifeexperience C.mayberegardedasourheavyburden D.mustchangetheirattitudetothecommunity
由苯合成香料K和解热镇痛药物G的路线如下 已知 请回答 1芳香烃A中CH原子数之比是451molA在氧气中完全燃烧生成8molCO2A的分子式是A的结构简式是． 2B→K的反应类型是． 3B的结构简式是． 4D→E反应的化学方程式是． 5K与新制CuOH2悬浊液反应的化学方程式是． 6G与第5小题中反应的有机产物互为同分异构体含有相同的官能团且位置与F中官能团的位置相同G的结构简式是．
6分EachmorningGrandpawasupearlysittingatthekitchentablereadinghisbook.Hisgrandsonwantedtobejustlikehimandtriedtocopyhimineverywayhecould.OnedaythegrandsonaskedGrandpaItrytoreadthebookjustlikeyoubutIdon'tunderstanditandIforgetwhatIunderstandassoonasIclosethebook.Whatgooddoesreadingthebookdo? ThegrandpaquietlyturnedfromputtingcoalinthestoveandrepliedTakethiscoalbasketdowntotheriverandbringmebackabasketofwater.Theboydidashewastoldbutallthewaterleakedoutbeforehegotbacktothehouse.ThegrandpalaughedandsaidYou'llhavetomovealittlefasternexttimeandsenthimbacktotheriverwiththebaskettotryagain. Thistimetheboyranfasterbutagainthebasketwasemptybeforehereturned.Outofbreathhetoldhisgrandpathatitwasimpossibletocarrywaterinabasketsohewenttogetabucketinstead.ThegrandpasaidIdon'twantabucketofwater;Iwantabasketofwater.You'rejustnottryinghardenough. Theboyagaindippedthebasketintotheriverandranhardbutwhenhereachedhisgrandpathebasketwasemptyagain.OutofbreathhesaidGrandpait'suseless!Soyouthinkitisuseless?thegrandpasaidLookatthebasket. Theboylookedatthebasketandforthefirsttimeherealizedthatthebasketwasdifferent.Ithadbeentransformedfromadirtyoldcoalbasketandwasnowclean.Grandsonthat'swhathappenswhenyoureadthebook.Youmightnotunderstandorremembereverythingbutwhenyoureadityou'llbechangedinsideandout. 1.Whatpuzzledthegrandsonmostwas. A.whetheritwasusefultoreadbooks B.whyheforgotwhathereadsoon C.whatkindofbookhecouldunderstand D.howhecouldreadbookslikehisgrandpa 2.WhydidGrandpaaskhisgrandsontofetchabasketofwater? A.Totrainhimtorunfaster. B.Tocleanthedirtybasketintheriver. C.Topunishhimfornotreadingcarefully. D.Togethimtorealizetheuseofreadingbooks. 3.Whatlessoncanwelearnfromthestory? A.Theoldarealwayswiserthantheyoung. B.Itisfoolishtocarrywaterwithabasket. C.Readingbookscanchangeapersongradually. D.Youcan'texpecttorememberwhateveryouread.
下列离子方程式书写正确的是
实验室可以长期放置的试剂是
PM2.5是指大气中直径小于或等于2.5微米的颗粒物也叫可入肺颗粒物与肺癌哮喘等疾病的发生密切相关是灰霾天气的主要原因．它主要来自化石燃料的燃烧如机动车尾气燃煤等．下列与PM2.5相关的说法不正确的是
下列分离或提纯物质的方法正确的是
15分Agroupoffrogsweretravelingthroughthewoodsandtwoofthem1fallintoahole.Alltheotherfrogslookeddown.Whentheysawhowdeep2holewastheytoldthetwofrogsthattheywoulddiesoon. Atfirstbothofthetwofrogsdidn'tcaretheirwordsandtried3besttojumpoutofthehole.Theotherfrogskepttellingthemtostopbecausetheythoughttherewasnochance4jumpoutofsuchadeephole.Finallyoneofthetwofrogsbelievedthesewordsandgaveup.Hefelldownanddied. Theotherfrogcontinuedtojumpashardashecould.Onceagainthecrowdoffrogsshoutedathimtostopthepainandjustdie.Hejumpedeven5hardandfinallysucceeded.WhenhegotouttheotherfrogsaskedDidn'tyouhearus?6theirgreatsurprisethefrogturnedouttobedeaf.Hethoughttheywerehelpinghimallthetimenot7stophim. Thisstoryteachestwolessons:Thereispoweroflifeanddeathinthetongue.Well﹣meantwordscanhelppeopleintrouble.Butevilwordssometimescankillthem.Becarefulof8yousay. Rememberthepowerofwords.Anyonecanspeakwords9arelikelytomakepeoplegiveupindifficult10time. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
设NA表示阿伏加德罗常数下列叙述中正确的是
下列热化学方程式或离子方程式正确的是
6分Noonewouldmuchliketheideaofeating61poundsoftomatoesaday.Butiftheirgoodnesswasputintoaneasy﹣to﹣swallowpillthatyouweretoldmightpreventstrokes中风andheartattacksyouwouldprobablybeputtinginanordertomorrow. Researchersbelievetheymayhavecomeupwithjustthataftertrials.Thedailypillcontainsachemicalcalledlycopenewhichmakestomatoesredandisknowntobreakdownfatinthevessels血管.ACambridgeUniversitystudyfoundtakingthepillsimprovedbloodflowandtheliningofvesselsinpatientswithpre﹣existingheartconditions.Italsoincreasedtheflexibilityoftheirvesselsby50percent.Thescientistsbelieveitcouldlimitthedamagecausedbyheartdisease﹣responsiblefor180000deathsayear﹣andhelpcutthe49000deathsayearfromstrokes.Theyalsohopeitcouldbenefitthosewitharthritis关节炎diabetes糖尿病andevenslowtheprogressofcancer. Eachpillisequaltoeatingaround61poundsofripetomatoes.StudieshaveshowneatingaMediterranean﹣styledietrichintomatoesfishvegetablesnutsandoliveoilcansignificantlyreducecholesterol胆固醇andhelppreventcardiovasculardisease. Preliminaryresultsfromatwo﹣monthtrialinwhichthepillwasgivento36heartdiseasepatientsand36healthyvolunteerswithanaverageageof67werepresentedatameetingoftheAmericanHeartAssociation.Itwasshowntoimprovethefunctionoftheendothelium﹣thelayerofcellsliningbloodvessels.Italsoimprovedtheirsensitivitytonitricoxidethegaswhichcausestheenlargementofthevesselsinresponsetoexercise. IanWilkinsonheadofCambridgeUniversity'sclinicaltrialsunitsaidTheseresultsarepotentiallyverysignificantanditmeetsthegoalbutweneedmoretrialstoseeiftheytranslateintofewerheartattacksandstrokes. Furtherstudiesareplannedwithresearchershopingitcouldofferachoiceforheartdiseasesuffererswhocannottakethecholesterol﹣lowingdrugs. MikeKnaptonheadoftheBritishHeartFoundationsaidAlthoughthisshowedlycopeneimprovedbloodflowinpeoplewithheartdiseasethat'salongwayfromdemonstratingthattakingitcouldimproveoutcomesforpeoplewithheartdisease.Thebestwaytogetthebenefitsofagooddietistoeatplentyoffreshfruitandvegetables. 1.WhatcanweinferfromParagraph1? A.Wecaneattoomuchtomatofood. B.Tomatoesarehelpfultostrokesandheartattacks. C.Tomatoeswilllosehealthyelementswereputintopills. D.Wehadbetternoteattomatoes. 2.Wecanlearnfromthepassagethatthepills. A.areattheexperimentstage B.cancureallthedisease C.arewidelyusedamongpatients D.costpatientssolittlemoney 3.WhatWasIanWilkinson'sopiniononthetrial? A.Disappointing. B.Surprising. C.Satisfactory. D.Terrible.
下列关于合成材料的说法中不正确的是
如图所示的实验能达到实验目的是
25分假定你是希望中学学生李华得知2017年香港大学要在大陆进行自主招生的消息后有意向香港大学申请参加自主招生考试请用英语写一封自荐信主要包括:1.个人信息2.性格爱好与特长3.学习情况注意:1.词数100左右;2.信的开头已为你写好不计入总词数;3.可根据内容要点适当增加细节以使行文连贯.4.参考词汇:自主招生independentrecruitmentDearSirMynameisLiHuafromHopeHighSchool.YoursLiHua.
三聚氰胺化学式C3N6H6是一种非食品类的重要有机化工原料广泛用于塑料造纸建材等行业．下图是我国科技工作者研制的以尿素为原料生产三聚氰胺的工艺﹣﹣“常压气相一步法联产纯碱新技术” 已知①尿素的熔点是132.7℃常压下超过160℃即可分解 ②三聚氰胺的熔点是354℃加热易升华微溶于水 ③以尿素为原料生产三聚氰胺的原理是6CONH22C3N6H6+6NH3+3CO2 请回答 1尿素是一种常用含氮量最高的化肥其氮元素的质量百分数为在实验室使其熔化的容器名称叫． 2工业上合成尿素的化学反应方程式为反应条件可以不写 3写出各主要成份的化学式产品1产品2X 4联氨系统沉淀池中发生的化学反应方程式为 5为了使母液中析出更多的产品2常用的方法是 A加入固体NaClB加入固体NaHCO3C通入CO2气体D通入NH3 6若生产过程中有4%的尿素损耗每吨尿素可生产三聚氰胺吨副产品纯碱吨．精确到0.001
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