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碳酸氢钠溶液和硫酸亚铁溶液混合过滤洗涤干燥得到碳酸亚铁在空气中灼烧碳酸亚铁得到铁的氧化物M． 某学习小组设计多种方案测定M的化学式． 方案Ⅰ．滴定法 ①称取7.84g样品M溶于足量的稀硫酸并配成100mL溶液A． ②取20.00mL溶液A于锥形瓶中滴加KSCN溶液溶液变红色再滴加双氧水至红色刚好褪去同时产生气泡． ③待气泡消失后用1.0000mol•L﹣1KI标准溶液滴定锥形瓶中的Fe3+达到滴定终点时消耗KI标准溶液20.00mL． 方案Ⅱ．重量法 a取3.92g样品M溶于足量盐酸微热至固体完全溶解 b向a溶液中通入足量的氯气充分反应 c向b溶液中滴加过量的氯氧化钠溶液充分搅拌 d过滤洗涤干燥灼烧称重得到氧化铁的质量为ag． 1方案Ⅰ必需的定量仪器有量筒托盘天平和． 2方案Ⅰ在滴定之前必须进行的操作包括用标准KI溶液润洗滴定管．根据数据计算M的化学式为． 3方案Ⅰ的步骤②中“气泡”有多种可能完成下列猜想 ①提出假设 假设1气泡可能是SCN﹣的反应产物N2CO2SO2或N2CO2． 假设2气泡可能是H2O2的反应产物 理由是． ②设计实验验证假设1 试管Y中的试剂是． 4方案Ⅱ中漏掉步骤b能否达到实验目的用化学方程式表示理由． 5根据方案Ⅰ的实验结果推测方案Ⅱ中a的理论值为． 6根据上述实验结果写出碳酸亚铁在空气中灼烧的化学方程式．
用乙烯甲苯E三种原料合成高分子药物M和有机中间体L的路线如图 已知 Ⅰ． Ⅱ． Ⅲ．有机物L是一种六元环酯M的分子式是C15H16O6n． 1C中含氧官能团的名称是D的结构简式是． 2H→J的反应类型是． 3H→L的化学方程式是． 4K→M属于加聚反应K的结构简式是． 5写出一定量的C与足量NaOH溶液反应的化学方程式． 6写出一种符合下列条件的C的同分异构体的结构简式． ①属于芳香族化合物②能发生银镜反应③遇FeCl3溶液能发生显色反应④核磁共振氢谱上有4组峰且峰面积之比为1122． 7已知．以CH3CH＝CH2为原料其他原料自选结合上述流程合成丙烯酸CH2＝CHCOOH写出合成路线．
下列关于有机物的说法正确的是
如图PA垂直于⊙O所在平面ABCAB为⊙O的直径PA＝AB＝2C是弧上的一个动点不与端点AB重合E为PC上一点且AE⊥PCF是线段BP上的一个动点不与端点B重合． 1求证AE⊥平面PBC 2若C是弧的中点∠BOF是锐角且三棱锥F﹣BOC的体积为求tan∠BOF的值．
我国科学家在天然气脱硫研究方面取得了新进展利用如图1装置可发生反应H2S+O2═H2O2+S↓甲池中发生如图2反应．下列关于该装置工作时的说法错误的是
若=0则x的值是
若执行如图所示的程序框图则输出S的值为
统计某校n名学生的某次数学同步练习成绩满分150分根据戒绩分数依次分成六组[90100[100110[110120[120130[130140[140150]得到频率分布直方图如图所示若不低于140分的人数为110则以下说法正确的是 ①m＝0.031②n＝800③100以下的人数为60④分数在区间[120140的人数占大半
已知函fx＝sinωx+φ+ω＞0|φ|＜的图象的相邻对称轴间的距离为函数fx在上单调递增在上单调递减则函数fx的解析式为．
Chinesehigh﹣speedrailwaysareavery.1comfortwaytotravel.Theyarecleanquietandefficient.Chinahasledotherdevelopingcountriesandevensomedevelopedonesinthisfieldsincethefirsthigh﹣speedtrain2comeintousein2008. Thestationsare3mainbuiltoutsidethetowncenterbutlocaltransporthasbeenlengthened4connectthehigh﹣speednetwork.Thefacilitiesonthetrainarenewandthestaffarewelltrained.Eventhesecondclass5chairprovideplentyofspace.Thepassagesaresowide6youcanmovewithoutdisturbinganyone.Youcanuseyourmobilephoneaccess7Internetorworkonyourlaptop.Thereisalsoarestaurantcarthoughthekindsoffood8belimited.Thetoiletsarclargecleananduser﹣friendlytoo.Thetrainalmostdoesn'trock.Evenwhenthetrainbrakesyoucanhardlyfeelitshake. What'smorewithafastercheck﹣inthehigh﹣speedtrainarealso9littleaffectedbyweatherthanplanes.Seldomare10delayedorcancelledforweathercondition.Thereforetheyhavebecomethefirstchoiceformanypassengers.
下列装置所示的实验中能达到实验目的是
氢能是发展中的新能源它的利用包括氯的制备应用等环节．回答下列问题 1氢气的制备 以太阳能为热源热化学硫碘循环分解水是一种高效无污染的制氢方法．其反应过程如图所示．反应Ⅱ包含两步反应 ①H2SO41＝SO3g+H2Og△H＝177kJ/mol ②2SO3g＝2SO2g+O2g△H＝196kJ/mol 写出反应Ⅱ的热化学反应方程式 2氯气的应用 CO2加氢制备甲酸HCOOH可用于回收利用CO2．温度为T1时将等物质的量的CO2和H2充入体积为1L的密闭容器中发生反应CO2g+H2g⇌HCOOHg△H化学平衡常数K＝1 实验测得v正＝k正•cCO2•cH2v逆＝k逆•cHCOOHk正k逆为速率常数． ①当CO2的转化率为33.3%时HCOOH的体积分数为保留整数． ②T1时k逆＝用k正表示．当升高温度至T2时k逆＝0.9k正则△H0填“＞”“＜“或“＝”． ③采用电还原法也可将CO2转化为甲酸根用Sn为阴极Pt为阳极KHCO3溶液为电解液进行电解．CO2应通入区填“阳极”或“阴极”其电极反应式为 ④可用NaHCO3代替CO2作为碳源加氢制备甲酸．向反应器中加入NaHCO3水溶液A1粉Cu粉在300℃下反应．NaHCO3用量一定时AlCu的用量对碳转化量影响结果如图．由图可知曲线d相对其它三条曲线碳转化量变化不大的主要原因是当碳转化量为30%时所采用的实验条件是．
阅读下面短文根据其内容写一篇60词左右的内容概要. Althoughbeingfamousmightsoundlikeadreamcometruetoday'sstars.feelinglikezooanimals.facepressuresthatfewofuscanimagine.Theyareatthecenterofmuchoftheworld'sattention.Paparazzi狗仔队campoutsidetheirhomescamerasready.Tabloids小报publishthrillingstoriesabouttheirpersonallives.Justimaginenotbeingabletodoanythingwithoutbeingphotographedorinterruptedforasignature.AccordingtopsychologistChristinaVillarrealcelebrities﹣famouspeople﹣worryconstantlyabouttheirpublicappearance.Eventuallytheystarttolosetrackofwhotheyreallyareseeingthemselvesthewaytheirfansimaginethemnotasthepeopletheywerebeforeeveryoneknewtheirnames.OvertimeVillarrealsaystheyfeelseparatedandlonely. Thephenomenonoftrackingcelebritieshasbeenaroundforages.Inthe4thcenturyB.C.paintersfollowedAlexandertheGreatintobattlehopingtopicturehisvictoriesforhisadmirers.WhenCharlesDickensvisitedAmericainthe19thcenturyhissold﹣outreadingsattractedthousandsoffans.leadinghimtocomplainabouthislackofprivacy.Tabloidsofthe1920sand1930sranarticlesaboutfilm﹣starsinmuchthesamewaythatmoderntabloidsandwebsitesdo. Beingapublicfiguretodayhowever.isalotmoredifficultthanitusedtobe.Superstarscannotmoveaboutwithoutworryingaboutphotographerswithmoderncameras.WhentheysaysomethingsillyordosomethingridiculousthereisalwaystheInternettospreadthenewsinminutesandkeeptheirstoryaliveforever. Iffameissotroublesomewhyaren'tallcelebritiesrunningawayfromit?Theansweristhattherearestillwaystodealwithit.Somestarsstaycalmbysurroundingthemselveswithtrustedfriendsandfamilyorbyescapingtoremoteplacesawayfrombigcities.Theyfocusnotonhowfamoustheyarebutonwhattheylovetodoorwhatevermadethemfamousinthefirstplace.Sometimesafewcelebritiescangetalittlejustice.Stillevenstarswhoenjoyfulljusticeoftencomplainabouthowhardtheirlivesare.Theyaretiredofbeingfamousalready.
已知复数z＝为虚数单位则|z|＝
已知椭圆Ca＞b＞0的离心半为F1F2分别是其左右焦点且过点A． 1求椭圆C的标准方程 2求△AF1F2的外接圆的方程．
已知向量＝2m＝31若∥则实数m的值为
在平面直角坐标系xOy中直线的参数方程为为参数以坐标原点为极点x轴的非负半轴为极轴且取相同的单位长度建立极坐标系圆C的极坐标方程为ρ＝2sinθ． 1求直线l的普通方程与圆C1的直角坐标方程 2设动点A在圆C1上动段OA的中点P的轨迹为C2C2与直线l交点为MN且直角坐标系中M点的横坐标大于N点的横坐标求点MN的直角坐标
已知函数若在区间[﹣11]上方程fx＝1只有一个解则实数m的取值范围为．
在四棱维P﹣ABCD中底面ABCD是正方形顶点P在底面的射影是底面的中心且各顶点都在同一球面上若该四校锥的灯棱长为体积为4且四棱的高为整数则此球的半径等于参考公式a3﹣b3＝a﹣ba2+ab+b2
7.5分PeoplehavegrowntalleroverthelastcenturywithSouthKoreanwomenshootingupbymorethan20cmonaverageandIranianmengaining16.5cm.Aglobalstudylookedattheaverageheightof18﹣year﹣oldsin200countries1914and2014.TheresultsshowthatwhileSwedeswerethetallestpeopleintheworldin1914Dutchmenhaverisenfroml2thplacetoclaimtopspotwithanaverageheightof182.5cm.Larvianwomenmeanwhilerosefrom28thplacein1914tobecomethetallestintheworldacenturylaterwithanaverageheightof169.8cm.JamesBenthamaco﹣authoroftheresearchsaystheglobaltrendislikelybutonceyouaverageoverwholepopulationsgeneticsplaysalesskeyroleheadded. Butwhileheighthasincreasedaroundtheworldthetrendinmanycountriesofnorthandsub﹣SaharanAfricacausesconcernsaysElioRiboliofImperialCollege.WhileheightincreasedinUgandaandNigerduringtheearly20thcenturythetrendhasreversedinrecentyearswithheightdecreasingamong18﹣year﹣olds. Onereasonforthesedecreasesinheightistheeconomicsituationinthe1980ssaidProfessorAlexander.Thenutritionalandhealthproblemsthatfollowedthepolicyofstructuraladjustmenthesaysledtomanychildrenandteenagersfailingtoreachtheirfullpotentialintermsofheight. Benthambelievestheglobaltrendofincreasingheighthasimportantimplications.Howtallwearenowisstronglyinfluencedbytheenvironmentwegrewupinhesaid.Ifwegivechildrenthebestpossiblestartinlifenowtheywillbehealthierandmoreproductivefordecadestocome. 1WhatcanbelearnedfromParagraphI? A.Theincreaseinwomen'sheightismuchbiggerthanmen'sinthelastcentury. B.Thelastcenturyhasseenagreatincreaseinpeople'sheightinmostcountries. C.Geneticsplaysakeyroleintheincreaseofpeople'sheightinthelastcentury. D.DutchandSwedesarerankedfirstandsecondinheightintheworldnowadays. 2TheunderlinedwordreversedinParagraph2canbereplacedby. A.sloweddown. B.goneupwards. C.changedtothecontrary. D.cometolifeagain. 3AccordingtothetextJamesBenthamsuggeststhat. A.Theeconomicsituationofsomecountriesshouldbeimproved. B.Environmentprotectionshouldbeattachedgreatimportanceto. C.Theglobaltrendofincreasingheightshouldbecloselywatched. D.Children'spropernutritionandhealthcareshouldbeguaranteed.
计算a25+a52的结果是
下列二次根式中与是同类二次根式的是
如果≈1.732≈5.477那么0.0003的平方根是．
假定你是李华你校拟组织美国交换生Chris等到泉州府文庙去参观请你写封邮件告知他活动安排.内容包括 1.集合时间和地点 2.内容参观府文庙间南古建筑观看木偶戏 3.预先准备简要了解孔子文化. 注意 1.可适当发挥使短文连贯通顺 2.文中不能出现考生的具体信息 3.词数100左右. 参考词汇1.府文庙theConfuciusTemple2.木偶戏puppetshow DearChris
Theworldisacolorfullandscapeofdifferentlanguagesskincolorsanddifferentcultures.It'simportanttohaveagoodunderstandingofdifferentculturesinordertobecomeawell﹣roundedperson1 Onewayistoreadhookswrittenbyauthorsfromaparticularculture.Readingworksbyauthorswhohaveacloserelationshipwithaparticularcultureallowspeopletogainanauthenticglimpseintothefoodmusiclanguagereligionandwayofalifeofaparticulargroupofpeople. 2 Anotherwaytolearnaboutdifferentculturesistotrytolearnaforeignlanguage.3Apersoncanchoosealanguageshehasalwayswantedtolearnandlocatelearningprogramstohelphermasterthelanguage.Besidesonecanenrollinaforeignlanguageclassinordertolearninamoreformalsetting.Onecanalsotrytovisitareasofthecitytoestablishsocialconnectionwithnativespeakersofthelanguage. 4Seekoutrestaurantsthatfeatureauthenticfoodfromavarietyofcountries.Foodisanimportantpartofdifferentculturesandallowspeopletogaindeepunderstandingintoaparticularculturalgroup'swayoflife. Communicatingwithpeoplefromothercountriesthroughemailorsnailmailisanotherusefulwaytobecomefamiliarwithdifferentcultures.5Variouswebsitesofferpenpalservicesofferingtoconnectindividualswithpenfriendsaroundtheworld. A.Storiesbasedonalocalcultureexposeonetoadifferentculture. B.Tryingauthenticfoodfromaspecificculturalgroupisalsoagreatidea. C.Thereareseveralwaystobecomeknowledgeableaboutdifferentcultures. D.Avarietyoflanguage﹣learningbookssoftwareandaudioprogramsisavailable E.TheInternethasmadeitpossibletocommunicatewithothersfromdifferentcountries. F.Makingcontactwithnativespeakersofthelanguageallowsonetogainfirsthandknowledge. G.Onewaytodevelopthisappreciationistotrytoteamaboutotherculturesaroundtheworld.
YoumaynotknowthenameJohnSmithPembertonbutyoumustknowthenameofhis1inventCoca﹣Cola. PembertonwasaUSchemist.WhenhewaswoundedintheCivilWarlieusedmedicinetocasethepainandgraduallygot2addicttoit.Tolighttheaddictionhecreatedhisowndrinkby3useleavesofcocaandnutsofkola.Henamed4Pemberton'sFrenchWineCoca.Inthesameyearthelocalgovernmentpassedabanonalcohol.Pembertonhadtochangetherecipetoremovethealcohol. In1886PembertoninvitedWillisVenabletohelphimperfecthisnewrecipe.Theyusedcarbonatedwaterandfinallyinventedanewdrink.Ithadnoalcohol5couldstilleasepainandclearthemind.Pembertondecidedtosellit6adrinkratherthanamedicine.In1887PembertonsoldpartofthestockofhiscompanytoAsaCandler7latercreatedtheCoca﹣ColaCompany. Nowadays.Coca﹣Colahasbecomeoneofthemostpopular8drinkintheworld.Thecompanyonlyofferssemi﹣finishedproductstopartnersandwon'tsellthe9originingredients成分.ItssecretrecipewaskeptintheSunTrustBankinAtlantafor86yearsuntiltheendof2011.Sincethenit10keepintheWorldofCoca﹣ColacenterinAtlanta.
某几何体的三视图如图所示则该几何体的体积是
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