首页
试卷库
试题库
当前位置:
X题卡
>
所有题目
>
题目详情
当光束通过下列分散系时,能产生丁达尔效应的是( )
查看本题答案
包含此试题的试卷
高三上学期化学《》真题及答案
点击查看
你可能感兴趣的试题
当平行光束通过下列分散系时能产生丁达尔效应的是
白酒
食醋
豆浆
矿泉水
当光束通过下列分散系①有尘埃的空气②稀硫酸③蒸馏水④墨水能观察到丁达尔效应的是
①②
②③
①④
②④
当光束通过下列分散系时能观察到丁达尔效应的是
盐酸
Fe(OH)
3
胶体
氯化钠溶液
CuSO
4
当光束通过下列分散系时可能产生丁达尔效应的是
NaCl溶液
Fe(OH)
3
胶体
盐酸
泥土溶液
当光束通过下列分散系时能产生丁达尔效应的是
豆浆
食盐水
碘酒
蔗糖水
当光束通过下列分散系时能观察到丁达尔效应的是
蒸馏水
盐酸
NaCl 溶液
Fe (OH)
3
胶体
当光束通过下列分散系时能观察到丁达尔效应的是
泥水
盐酸
NaCl 溶液
Fe (OH)
3
胶体
当光束通过下列分散系时能产生丁达尔效应的是
溶液
澄清石灰水
胶体
KOH溶液
当光束通过下列分散系时能产生丁达尔效应的是
NaCl 溶液
Fe(OH)
3
胶体
盐酸
水
光束通过下列分散系能产生丁达尔效应的是
白酒
食醋
豆浆
矿泉水
当光束通过下列分散系时能观察到丁达尔效应的是
蔗糖溶液
盐酸
氯化钠溶液
Fe (OH)
3
胶体
当光束通过下列分散系时能观察到丁达尔效应的是
NaCl溶液
盐酸
豆浆
蒸馏水
当光束通过下列分散系①有尘埃的空气②稀硫酸③水④墨水能观察到丁达尔效应的是
①②
③④
①④
②④
当光束通过下列分散系时能观察到丁达尔效应的是
NaCl溶液
盐酸
碘酒
Fe(OH)
3
胶体
当光束通过下列分散系①有尘埃的空气②稀硫酸③蒸馏水④墨水能观察到丁达尔效应的是
①④
②③
①②
②④
当光束通过下列分散系时不能产生丁达尔效应的是
雾
稀豆浆
氢氧化铁胶体
硫酸铜溶液
当光束通过下列分散系时能观察到丁达尔效应的是
盐酸
Fe(OH)
3
胶体
NaCl溶液
CuSO
4
溶液
当光束通过下列分散系时能观察到丁达尔效应的是
淀粉溶液
泥水
NaCl 溶液
浓盐酸
当光束通过下列分散系时能观察到丁达尔效应的是
泥水
盐酸
NaCl 溶液
Fe (OH)3 胶体
当光束通过下列分散系时能产生丁达尔效应的是
蔗糖水
食盐水
豆浆
小苏打水
热门试题
更多
Ablackholeisaspotinspacethathas1powergravity.Itsgravityissostrongthatitpullseverythingnearbyintoitstarsplanetsandotherthings.Blackholesformwhenastardies.Whenthathappensahugeamountofmattercrowdsintoaverysmallspace2becomesverydense.Blackholes3talkaboutin1783first.Thatyearonescientistsaidthatintheuniversetheremightbeplaceswithstronggravitytotraplightalthoughhedidn'tusethetermblackhole.
室温下下列各组离子在指定溶液中能大量共存的是
NewAppHelpsPeopleRememberFaces Largegatheringssuchasweddingsandconferencescanbesociallyoverwhelming.Pressuretolearnpeople'snamesonlyaddstothestress.Anewfacial﹣recognitionappcouldcometotherescuebutprivacyexpertsrecommendproceedingwithcaution. TheappcalledSocialRecallconnectsnameswithfacesviasmartphonecamerasandfacialrecognitionpotentiallyavoidingtheneedforformalintroductions.ItbreaksdownthesesocialbarriersweallhavewhenmeetingsomebodysaysBarrySandrewwhocreatedtheappandtesteditataneventattendedbyabout1000people. AfterreceivinganinvitationtodownloadSocialRecallfromaneventorganizertheuserisaskedtotaketwoselfiesandsigninviasocialmedia.Attheeventtheappisactivewithinapreviouslydefinedgeographicalarea.Whenauserpointshisorherphonecameraatanattendee'sfacetheappidentifiestheindividualdisplaystheperson'snameandlinkstohisorhersocialmediaprofile.Toprotectprivacyitrecognizesonlythosewhohaveagreedtoparticipate.Andtheapp'screatorssayitautomaticallydeletesusers'dataafteranevent. AnnCavoukianaprivacyexpertwhorunsthePrivacybyDesignCenterofExcellencepraisestheapp'screatorsfortheseprotectivemeasures.Shecautionshoweverthatwhenpeoplechoosetosharetheirpersonalinformationwiththeapptheyshouldknowthattheremaybeunintendedconsequencesdowntheroadwiththatinformationbeingusedinanothercontextthatmightcomebacktobiteyou. Thestart﹣uphasalsodevelopedaversionoftheappforindividualswhosufferfromprosopagnosiaorfaceblindnessaconditionthatpreventspeoplefromrecognizingindividualstheyhavemet.Tousethisappapersonfirstacquiresanimageofsomeone'sfacefromeitherthesmartphone'scameraoraphotographandthentagsitwithaname.Whenthecameraspotsthatsamefaceinreallifethepreviouslyenteredinformationisdisplayed.Thecollecteddataarestoredonlyonauser'sphoneaccordingtotheteambehindtheapp. 1SocialRecallisusedto. A.takephotos B.identifypeople C.organizeevents D.makefriends 2Paragraph3ismainlyabout. A.howtheappworks B.howtheappwascreated C.whatmakestheapppopular D.whatpeoplecandowiththeapp 3SocialRecallhelpspeoplewithprosopagnosiaby. A.givingnamestothephotoskeptintheirsmartphones B.collectinginformationpreviouslyenteredinthephone C.providingtheinformationofapersonwhentheyfirstmeet D.showingtheperson'sinformationwhenitspotsastoredface 4WhatcanwelearnaboutSocialRecallfromthepassage A.Itmayputpeople'sprivacyatrisk. B.Ithascausedunintendedconsequences. C.Itcanpreventsomecommunicationdisorders. D.Itispraisedbyusersforitsprotectivemeasures.
RayTokudaa54﹣year﹣oldJapaneseAmericanisproudofthetitlehisschoolhasgivenhim.HeisaShifuaChinesewordliterallymeaningamastermentororseniorpractionerofmartialarts. Tokudahasreasontobeproud.HehasbeeninvolvedwithChinesemartialartsforalmostfourdecades.AfterlearningthematthemartialartsschoolinNewMexicoStatetodayheisamongthemostexperiencedkungfuteachersoftheschool. PracticingmartialartstwotothreehoursandhelpingstudentsimprovetheirskillshavebecomeTokuda'sdailyroutine.Heexpectstopracticeandteachmartialartsfortherestofhislife.I'mstilllearning.It'sworthmorethanalifetimetolearnChinesemartialartshesaid.OnceIstartedIjustcouldn'tstop.Ithinkit'salsothemagicofChineseculture. Tokudawassenttothemartialartsschoolwhenhewas10.Hestillremembershowunwillinghewaswhenstartingout.MyfatherhadalwayswantedtolearnChinesemartialartsbutnevergotthechancesoheputhiskidinhesaid.IwassoafraidatthattimebecauseIthoughtkungfuwasallaboutfighting. Butthingschangedafterhelearnedthatmartialartsweremorethanpunchingandkicking. OneofthethingsmartialartsteachmeisovercomingadversityTokudasaid.AsalittlekidmyfirstlessonwaslikeohlookthisisathingthatIcangetthroughbydiligenceperseverance毅力anddedicationandthatwaspricelessformylife. LearningChinesemartialartsopenedagatewayforhimtobetterunderstandChineseculturebecausehecouldhearalotofancientChinesekungfu﹣relatedstories.ItislikeinAmericawherewehearstoriesaboutknightsinshiningarmorandKingArthurandnobledeedsdonehesaid.IfeelmartialartspreservesomethingofancientChinathatcan'tbefoundinbooks.Theyaresortofanoralhistory. TokudahasalsobeeninvitedtovariouseventsinhishomestatetoshowcasetraditionalChinesecultureincludingthedragondanceandliondancewhichhealsolearntatthemartialartsschool.Becauseofthisheisnowconsideredaculturalenvoy使者intheeyesofthepublic. 1Tokudadidn'twanttolearnkungfubecausehehadthoughtitwas. A.practical B.magical C.violent D.difficult 2FromthepassagewhatcanwelearnaboutTokuda A.Helearntmartialartsfromhisfather. B.Heisthefounderofthekungfuschool. C.Helearntfrommartialartshowtodealwithdifficulties. D.Heisthemostexperiencedkungfuteacherofhisstate. 3WhichofthefollowingwordscanbestdescribeTokuda A.Modestandfriendly. B.Devotedandpersevering. C.Talentedandhumorous. D.Motivatedandconsiderate.
OldTomhadfoursons.Hewantedthem1learnnottojudgethingstooquickly.Sohesentthemtolookatanappletreeindifferentseasons.Thefirstsonwentinwinterthesecondinspringthethirdinsummerandtheyoungestinautumn.Whentheyallcamebackhecalledthemtogethertodescribe2theyhadseen.Thesonshaddifferent3opinion.Tomthentoldthemthattheyshouldn'tjudgeatreeorapersonbyonlyoneseason.
Smile!Itmakeseveryoneintheroomfeelbetterbecausetheyconsciouslyorunconsciouslyaresmilingwithyou.Growingevidenceshowsthataninstinctforfacialmimicry模仿allowsustoempathizewithandevenexperienceotherpeople'sfeelings.Ifwecan'tmirroranotherperson'sfaceitlimitsourabilitytoreadandproperlyreacttotheirexpressions.AreviewofthisemotionalmirroringappearsonFebruary11inTrendsinCognitiveSciences. IntheirpaperPaulaNiedenthalandAdrienneWoodsocialpsychologistsattheUniversityofWisconsindescribehowpeopleinsocialsituationscopyothers'facialexpressionstocreateemotionalresponsesinthemselves.Forexampleifyou'rewithafriendwholookssadyoumighttryonthatsadfaceyourselfwithoutrealizingyou'redoingso.Intryingonyourfriend'sexpressionithelpsyoutorecognizewhatthey'refeelingbyassociatingitwithtimesinthepastwhenyoumadethatexpression.Humansgetthisemotionalmeaningfromfacialexpressionsinamatterofonlyafewhundredmilliseconds. Youreflectonyouremotionalfeelingsandthenyougeneratesomesortofrecognitionjudgmentandthemostimportantthingthatresultsinisthatyoutaketheappropriateaction﹣youapproachthepersonoryouavoidthepersonNiedenthalsays.Yourownemotionalreactiontothefacechangesyourperceptionofhowyouseethefaceinsuchawaythatprovidesyouwithmoreinformationaboutwhatitmeans. Aperson'sabilitytorecognizeandshareothers'emotionscanbepreventedwhentheycan'tmimicfaces.Thisisacommoncomplaintforpeoplewithmotordiseaseslikefacialparalysis瘫痪fromastrokeorevenduetonervedamagefromplasticsurgery.Niedenthalnotesthatthesamewouldnotbetrueforpeoplewhosufferfromparalysisfrombirthbecauseifyou'veneverhadtheabilitytomimicfacialexpressionsyouwillhavedevelopedcompensatorywaysofinterpretingemotions. Peoplewithsocialdisordersassociatedwithmimicryoremotion﹣recognitiondamagelikeautism自闭症canexperiencesimilarchallenges.TherearesomesymptomsinautismwherelackoffacialmimicrymayinpartbeduetolimitationofeyecontactNiedenthalsays. Niedenthalnextwantstoexplorewhatpartinthebrainisfunctioningtohelpwithfacialexpressionrecognition.Abetterunderstandingofthatpartshesayswillgiveusabetterideaofhowtotreatrelateddisorders. 1Accordingtothepassagefacialmimicryhelps. A.experienceone'sownfeelingsclearly B.changeothers'emotionsquickly C.respondtoothers'expressionsproperly D.developfriendshipwithotherseasily 2WecanknowfromParagraph4and5that. A.peoplewithmotordiseasesmayalsosufferfromautism B.peoplebornwithfacialparalysismaystillrecognizeemotions C.peoplewithsocialdisorderscan'thaveeyecontactwithothers D.peoplereceivingplasticsurgeryhavedifficultyinmimickingfaces 3AccordingtoNiedenthalthenextstepofthestudywillfocuson. A.howwecantreatbraindisorders B.whatcanbedonetoregainfacialmimicry C.howourbrainhelpsuswithemotionalmirroring D.whatpartofourbrainhelpsrecognizefacialexpression 4Thepassageiswrittento. A.discusshowpeoplereactpositivelytoothers'smiles B.drawpeople'sattentiontothosewithsocialdisorders C.introduceanewtrendinfacialexpressionrecognition D.explainhowemotionalmirroringaffectspeople'sempathy
稀土元素包括元素周期表中的镧系元素以及与镧系元素化学性质相似的钪Sc和钇Y元素.请回答下列问题 1镧系元素位于元素周期表第族镧系元素位于周期表的区. 2基态钪原子的价电子排布式为. 3大多数稀土元素的金属离子易与乙二胺H2NCH2CH2NH2等配位乙二胺中价层电子对数为4的原子为填元素符号乙二胺和三乙胺[CH3CH23N]均属于胺类但是乙二胺比三乙胺的沸点高得多其原因是. 4稀土元素最常见的化合价为+3价但也有少数还有+4价请根据图1的电离能数据判断图30中最可能有+4价的元素是填元素符号在加热条件下其低价氯化物易发生水解其无水低价氯化物可用加热含六个结晶水的低价氯化物和NH4Cl固体混合物的方法来制备.其中NH4C1的作用是. 5镱Yb是电脑记忆元件的重要元素其单质晶胞结构如2所示晶胞中镱原子的配位数为若晶胞边长为apm镱原子半径为pm阿伏加德罗常数的值为NA则镱单质的密度为g•cm﹣3用含aNA的代数式表示.
Everyone1lovesnow.Butwhenschoolstaysopendespitethesnowitcanbereallyannoying.Howeverthereisoneupsideofgoingtoschool2acoldwinterdayyoumightbesmarter.Sofarresearcherswhostudythebrain3findthatcoldtemperaturesmakeusthinkmorequicklysincemessagestravelfasteramongourbraincells.Sothescientistssay4hangoutonacoldmorningmayboosttheresultofanytestthatday.
SO2NO是大气污染物NH4NO3H2SO4等是水体污染物有效去除这些污染物是一项重要课题. 1NOSO2可以先氧化后用碱吸收.其氧化过程的反应原理如下 NOg+O3g⇌NO2g+O2g△H1=﹣200.9kJ•mol﹣1 SO2g+O3g⇌SO3g+O2g△H2=﹣241.6kJ•mol﹣1 2SO2g+O2g⇌2SO3g△H3=﹣196.6kJ•mol﹣1 则反应2NO2g⇌2NOg+O2g的△H=kJ•mol﹣1. 2土壤中的硫循环如图1所示土壤中的黄铁矿FeS2在过程Ⅰ中会转化成硫酸亚铁和硫酸该过程发生的化学方程式为某种反硫化细菌在过程Ⅱ中需要有乳酸参与反应消耗硫酸生成H2S并伴有热量放出那么乳酸除在反应中作还原剂外还存在另一作用并解释原因. 3电解法除去工业废水中的硝酸铵的装置示意图如图2所示阴极电极反应式为. 4向恒容密闭容器中充入1molNO和2molO3发生反应 NOg+O3gNO2g+O2g△H<0 不同温度下反应相同时间后体系中NO转化率随温度变化曲线如图3.温度低于100℃时NO转化率随温度升高而增大的主要原因是已知温度高时O3分解生成活性极高的氧原子NO转化率随温度升高而降低可能的原因有.
MyPerfectImperfectLife AfewyearsagoIwasstandingatthebarre扶手杠waitingformyadultballetclasswhenIheardavoicebehindme.Sodoyouhavethisperfectlife Myfirstreactionwasto1whowasbeingaskedsuchanoddquestion.ThenIrememberedtherewereonlytwoofusintheroom.WhenIturned2theotherwomanwaslookingstraightatme. Ihadnoideahowtoanswerit.Wasshe3WhohasaperfectlifeSureoccasionallyIdidfindtheperfectdressortheperfectpairofshoes4neverwouldIusethatwordtodescribeanythingaboutmeormylife.Ifeltatwingeofguiltforsomehowgivingherthat5. Shewatchedme.Ifinally6towhisperaquickNo. Bythentheteacherhadenteredtheroomandturnedonthemusictostartclass.Withasighof7Imovedmyfeetintothebestposition.ButassoonasmykneesbentforourfirstposeIrealizedmy8hadbeendisturbed.Thiswoman'swordswouldn't9echoinginmythoughts. Iwantedtoknowhowshecameupwithherverymistaken10.Ifsheknewanythingaboutmylifesheneverwouldhavehadthe11toaskmethatquestion. Ididmybesttodoourfloorexercisesinfrontofthemirror.ForafewmomentsIdidn'tseetheusual12ofmyolderselfattemptingtouseabeautifulartformto13mygracefulness.Ionlysawthelittlegirlwhosefatherdiedwhenshewastwothechildwhowalkedhomefromelementaryschooleverydaytoanemptyhousewholearnedtosewherownclothesto14money. Perfect.Mylifehadbeenfarfromit. Whenthosememories15IwasleftwithavisionofthewomanIhadbecomethewoman16byallthosethingsIconsideredimperfect.Inowsawthewomanwhohadlearnedtobeself﹣reliantwho17herfamilyandherfriendswhodidn'ttakelifeforgranted.Wasthattheperfectthiswomanhaddetected Istilldon'tknowbutInolongerfeel18orfeellikeImustkeeptrackofallthedifficulttimestoprovemylifeisn't19.IfeveragainaskedwhethermylifeisperfectIwouldhaveadifferent20.BecausenowIseethatdespiteallitsimperfectionitis. 1A.notice B.understand C.wonder D.expect 2A.up B.away C.over D.around 3A.fair B.serious C.anxious D.wise 4A.but B.or C.for D.and 5A.intention B.instruction C.impression D.information 6A.learned B.managed C.agreed D.planned 7A.sadness B.surprise C.pleasure D.relief 8A.concentration B.patience C.confidence D.effort 9A.escape B.keep C.stop D.stand 10A.idea B.advice C.reason D.theory 11A.right B.urge C.excuse D.honor 12A.reflection B.preference C.appearance D.expression 13A.experience B.describe C.replace D.improve 14A.collect B.earn C.spend D.save 15A.faded B.failed C.floated D.flashed 16A.buried B.shaped C.watched D.followed 17A.changed B.welcomed C.valued D.protected 18A.worried B.guilty C.cautious D.desperate 19A.comfortable B.ordinary C.perfect D.meaningful 20A.solution B.message C.approach D.answer
实验室以扑热息痛对乙酰氨基苯酚为原料经多步反应制甘素的流程如下 步骤Ⅰ非那西汀的合成 1将含有1.0g扑热息痛的药片捣碎转移至两颈烧瓶中.用滴管加入8mL1mol•L﹣1NaOH的95%乙醇溶液.开启冷凝水随后将烧瓶浸入油浴锅.搅拌达沸点后继续回流15min. 2将烧瓶移出油浴.如图所示用注射器取1.0mL的碘乙烷逐滴加入到热溶液中.继续将烧瓶置于油浴回流15min. 3将烧瓶从油浴中抬起取下冷凝管趁热用砂芯漏斗抽滤.滤去不溶的淀粉药片的填充物.将热滤液静置得到沉淀.用另一个砂芯漏斗过滤得到非那西汀固体. 步骤Ⅱ甘素的合成 1将非那西汀固体转移到圆底烧瓶中加入5mL6mol•L﹣1的盐酸.加热回流15min. 2加入NaHCO3调至pH为6.0~6.5再向反应液中加1.37g尿素和2滴乙酸.加热回流60min. 3移出烧瓶冷却有沉淀析出抽滤用冰水洗涤得到甘素. 1将药片捣碎所用的仪器名称为. 2实验中用油浴加热的优点是. 3使用砂芯漏斗抽滤的优点是且得到的沉淀较干燥. 4冷凝管的冷却水从填“a”或“b”端进. 5步骤Ⅱ中向热溶液中加入NaHCO3中和为避免大量CO2溢出加入NaHCO3时应. 6用冰水洗涤甘素固体的操作是.
用电解法处理含Cr2O72﹣的废水探究不同因素对含Cr2O72﹣废水处理的影响结果如表所示Cr2O72﹣的起始浓度体积电压电解时间均相同.下列说法错误的是 表
以硫酸渣含Fe2O3SiO2等为原料制备铁黄FeOOH的一种工艺流程如下 1“酸溶”中加快溶解的方法为写出一种. 2“还原”过程中的离子方程式为. 3①“沉铁”过程中生成FeOH2的化学方程式为. ②若用CaCO3“沉铁”则生成FeCO3沉淀当反应完成时溶液中cCa2+/cFe2+=. [已知KspCaCO3=2.8x10﹣9KspFeCO3=2×10﹣11] 4“氧化”时用NaNO2浓溶液代替空气氧化FeOH2浆液虽然能缩短氧化时间但缺点是. 5焦炭还原硫酸渣炼铁能充分利用铁资源在1225℃nC/nO=1.2时焙烧时间与金属产率的关系如图2时间超过15分钟金属产率下降的原因是.
化学的应用无处不在下列说法正确的是
短周期主族元素XYZW原子序数依次增大X位于第ⅣA族Y元素原子最外层电子数是次外层的3倍Z原子半径为同周期中最大W与Y同主族.下列说法正确的是
如图AE⊥平面ABCDCF∥AEAD∥BCAD⊥ABAB=AD=1AE=BC=2. Ⅰ求证BF∥平面ADE Ⅱ求直线CE与平面BDE所成角的正弦值 Ⅲ若二面角E-BD-F的余弦值为求线段CF的长.
设{an}是等差数列{bn}是等比数列.已知a1=4b1=6b2=2a2-2b3=2a3+4. Ⅰ求{an}和{bn}的通项公式 Ⅱ设数列{cn}满足c1=1cn=其中k∈N*. i求数列{ac-1}的通项公式 ii求aicin∈N*.
设NA为阿伏加德罗常数的值下列说法正确的是
用化学用语表示Na2O+2HCl═2NaCl+H2O中的相关微粒其中正确的是
假设你是红星中学高三学生李华请根据以下四幅图的先后顺序以ANewWaytoExploretheForbiddenCity为题用英语写一篇短文向校刊英语园地投稿记述上周末你带英国朋友Jim游览故宫的全过程. 注意词数不少于60. 提示词二维码QRcode
下列有关物质性质的叙述不正确的是
常温常压下将amolCO2气体通入含bmolNaOH的溶液中下列对所得溶液的描述正确的是
根据下列实验操作和现象所得出的结论正确的是
假设你是红星中学高三学生李华你的英国朋友Jim在给你的邮件中提到他暑假将来北京参加外国人唱中国歌大赛希望你为他推荐一首中文歌曲.请给他回邮件内容包括 1.推荐曲目 2.推荐理由 3.你的祝愿. 注意1.词数不少于50 2.开头和结尾已给出不计入总词数. DearJim Yours LiHua
GOINGTOUNIVERSITYissupposedtobeamind﹣broadeningexperience.Thatstatementisprobablymadeincomparisontotrainingforworkstraightafterschoolwhichmightnotbesoencouraging.ButisitactuallytrueJessikaGolleoftheUniversityofTübingeninGermanythoughtshewouldtrytofindout.Herresulthoweverisnotquitewhatmightbeexpected.AsshereportsinPsychologicalSciencethisweekshefoundthatthosewhohavebeentouniversitydoindeedseemtoleavewithbroaderandmoreinquiringmindsthanthosewhohavespenttheirimmediatepost﹣schoolyearsinvocational职业的trainingforwork.Howeveritwasnotthecasethatuniversitybroadenedminds.Ratherworkseemedtonarrowthem. Dr.Gollecametothisconclusionaftersheandateamofcolleaguesstudiedtheearlycareersof2095Germanyoungsters.Theteamusedtwostandardizedteststoassesstheirvolunteers.Onewasofpersonalitytraitsincludingopennessconscientiousness认真andsoon.Theotherwasofattitudessuchasrealisticinvestigativeandenterprising.Theyadministeredbothteststwice﹣oncetowardstheendofeachvolunteer'stimeatschoolandthenagainsixyearslater.Oftheoriginalgroup382wereontheintermediatetrackfromwhichtherewasachoicebetweentheacademicandvocationalroutesanditwasonthesethattheresearchersfocused.Universitybeckonedfor212ofthem.Theremaining170chosevocationaltrainingandajob. WhenitcametothesecondroundoftestsDr.Gollefoundthatthepersonalitiesofthosewhohadgonetouniversityhadnotchangedsignificantly.Thosewhohadundergonevocationaltrainingandthengotjobswerenotthatmuchchangedinpersonalityeither﹣exceptinonecrucialrespect.Theyhadbecomemoreconscientious. Thatsoundslikeagoodthingcertainlycomparedwiththecommonpublicimageofundergraduatesasabunchoflazybones.Butchangesinattitudethattheresearchersrecordedwereratherworrying.Intheuniversitygroupagainnoneweredetectable.Butthosewhohadchosenthevocationalrouteshowedmarkeddropsininterestintasksthatareinvestigativeandenterprisinginnature.Andthatmightrestricttheirchoiceofcareers. Someinvestigativeandenterprisingjobssuchasscientificresearchareindeedbeyondthedegreeless.ButmanyparticularlyinGermanywithitstraditionofvocationaltrainingarenot.Theresearchersmentionforexamplecomputerprogrammersandfinance﹣sectorworkersascareersrequiringthesetraits.IfDr.GolleiscorrectandchangesinattitudebroughtaboutbytheverytrainingGermanypridesitselfonarenarrowingpeople'schoicesthatisindeedamatterworthyofseriousconsideration. 1WhichofthefollowingcanbestreplacebeckonedforinParagraph2 A.Examined. B.Attracted. C.Organized. D.Recognized. 2Whatcanwelearnfromtheresearch A.Thedegreelesshavenotchangedinpersonalities. B.Goingtouniversityisamind﹣broadeningexperience. C.Workingstraightafterschoolnarrowspeople'sminds. D.Collegestudentspridethemselvesontheireducation. 3Accordingtothelasttwoparagraphs. A.collegestudentsenjoyaverygoodpublicimage B.theundergraduateshavechangedsignificantlyinattitude C.thedegreelessaremuchbetteratdealingwithchallengingtasks D.peopleshowlessinterestininvestigativejobsduetovocationaltraining 4Whatistheauthor'sattitudetowardsthefinding A.Concerned. B.Optimistic. C.Unclear. D.Sceptical.
下列说法正确的是
实验室以食盐为原料制备焦亚硫酸钠Na2S2O5并测定其纯度流程如下 已知①Na2SO3+SO2═Na2S2O55C2O42﹣+2MnO4﹣+16H+═10CO2↑+2Mn2++8H2O ②焦亚硫酸钠与强酸接触则放出SO2而生成相应的盐类. 1反应Ⅰ的化学方程式为流程中X的化学式为. 20.5molNa2S2O5溶解于水配成1L溶液该溶液pH=4.5.溶液中部分微粒浓度随溶液酸碱性变化如图所示写出Na2S2O5溶于水时主要反应的离子方程式为. 3为测定产品的纯度实验步骤依次为 步骤1准确称取20.00g产品于反应容器中加入稍过量的2mol•L﹣1的H2SO4溶液蒸馏将产生的SO2用200.00mL0.5000mol•L﹣1酸性KMnO4溶液吸收完全吸收后加水稀释得到吸收液250mL. 步骤2准确量取25.00mL吸收液用0.1000mol•L﹣1的K2C2O4标准溶液滴定消耗K2C2O4标准溶液48.00mL. 计算产品中焦亚硫酸钠Na2S2O5的纯度写出计算过程.
BenefitsofSports Doingsportsisaphysicalmentalandsocialadventure.It'sagreatwayforchildrentotakeabreakfromacademicsandreleaseextraenergy.Italsohelpsthemleadfullerandhappierlivesasregularsportshaveproventoimproveoverallwell﹣being. Thephysicalbenefitsofdoingsportsareprobablythemostobvious.Regardlessofyourfitnesslevelwhenyoustartplayingsportsyou'llnoticeanincreaseinyouroverallfitnessonceyou'reinvolved.1Basketballplayersfocusonstrengthtrainingfootballplayersworkonspeedwhiletrackathletestrainthroughlongerruns.Thetrainingprocesshelpspromotephysicalfitnessandperformancesincompetitions. 2Playingsportscontributestomentalhealthhelpingtoincreaseconfidenceandself﹣worth.Apatonthebackhigh﹣fivefromateammateorhandshakeafteramatchreallyboostsachild'sconfidence.Wordsofpraiseandencouragementfromthecoachparentsandotherplayersraisetheself﹣worth.3Soafteragameit'sabetterideatoaskDidyouenjoythegameratherthanDidyouwin Childrenwhoparticipateinsportsmightalsobenefitfromthesocialaspectfeelingpartofagroupbuildingupaccountabilityandleadership.4Teamworkinvolvesbothbeingdependableasateammateandlearningtorelyonyourteammatestoachieveapositiveoutcome.Teamworkbreedsaccountabilityandchallengesyoutoberesponsibleforyouractions.Beingpartofateamgivesyouanopportunitytobealeader. Disciplineisanothersocialadvantage.Mostorganizedsportsrequireastricttrainingandpracticeschedule.Asastudent﹣athleteyouneedtobalanceacademicsandathletics.5 Thereisnoshortageofreasonstofindasporttogetinvolvedin.AreyoureadytogoPickoneandgetmoving! A.It'snotjustyourbodythatbenefitsfromsports. B.Thereforeplayingsportsisgoingtomakeyoumorefit. C.Butrememberachild'sself﹣worthshouldnotbedistinguishedbyvictoryorloss. D.Ifyouplaygroupsportsyou'llbepartofateamthattakesdirectionfromacoach. E.Nearlyeverysportrequiresphysicalactivityandtheskillsneededtobecompetitive. F.Amongtheselearninghowtofunctionaspartofateamisthemostimportantadvantage. G.Onlywithstrictdisciplinecanyoubesuccessfulbothintheclassroomandinthesportsfield.
钼酸钠晶体Na2MoO4•2H2O是一种金属腐蚀抑制剂.工业上利用钼精矿主要成分是不溶于水的MoS2制备钼酸钠的两种途径如图所示 1Na2MoO4•2H2O中钼元素的化合价是. 2在途径Ⅰ中 ①为了提高焙烧效率除增大空气量外还可以采用的措施有焙烧后的尾气中含有SO2需要处理下列不能用作吸收剂的是填字母 a.CaOH2b.HNO3c.Na2CO3 ②焙烧生成MoO3也可以利用铝热反应回收金属钼写出该反应的化学方程式 ③碱浸时生成Na2MoO4和另一种气体A该气体A的电子式为碱浸后的钼酸钠溶液中cMnO42﹣=0.40mol•L﹣1cCO32﹣=0.10mol•L﹣1由钼酸钠溶液制备钼酸钠晶体时需加入BaOH2固体以除去CO32﹣当BaMoO4开始沉淀时CO32﹣的去除率是已知KspBaCO3=1.0×10﹣9KspBaMoO4=4.0×10﹣8忽略溶液的体积变化 ④Na2MoO4溶液重结晶得到的母液可以在下次重结晶时重复使用但达到一定次数后必须净化处理原因是“分析纯”的钼酸钠常用钼酸铵[NH42MoO4]和氢氧化钠反应来制取若将该反应产生的气体与途径Ⅰ所产生的气体一起通入水中得到正盐的化学式是. 3在途径Ⅱ中氧化时还有Na2SO4生成则反应的离子方程式为.
常温下在新制氯水中滴加NaOH溶液溶液中水电离出的氢离子浓度的对数lg[c水H+]与NaOH溶液的体积之间的关系如图所示下列推断正确的是
热门题库
更多
高三下学期物理
高三上学期物理
高三上学期生物
高三上学期化学
高二下学期化学
高二下学期生物
高三下学期生物
高三下学期化学
高三上学期英语
高二下学期英语
教案备课库
高三下学期英语
教案备课库
教案备课库
教案备课库
教案备课库