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归纳是学习化学常用的方法．下列归纳全部正确的是（ ）
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善于归纳和总结是科学的学习方法下列归纳正确的是
He、NO
2
、SO
2
是有害气体
煤、石油、天然气是化石燃料
塑料、纤维、橡胶是天然材料
钙、铁、镉、硒是微量元素
归纳与反思是学习化学的重要环节以下归纳全部正确的一组是
A
B
C
D
归纳是学习化学常用的方法．下列归纳全部正确的是
A
B
C
D
归纳与比较是学习化学的重要方法下列有关FeCl2和FeCl3的知识归纳不正确的是
组成：都是由铁元素和氯元素组成
性质：都与氢氧化钠溶液反应生成沉淀
制取：都可以用铁和稀盐酸反应来制取
分类：都属于盐类
及时对知识进行分类归纳是一种重要的学习方法下面是小洁同学以连线方式对相关主题知识进行归纳的情况其中完
化学与健康
物质的性质与用途
安全常识
化学与能源
对知识的归纳是学习化学的一种重要方法下列归纳正确的是
汽油和洗涤剂除油污的原理相同
空气、糖水、高锰酸钾都属于混合物
纯碱、烧碱都属于碱
只有当两种化合物互相交换成分，生成物中有沉淀或有气体或有水生成时，复分解反应才可以发生
归纳总结和逻辑推理是化学学习中常用的思维方法下列归纳推理正确的是
二氧化碳气体和氧气都能用浓H
2
SO
4
干燥
Na
2
CO
3
溶滚和NaNO
3
溶液都能使无色酚酞试液变红
稀有气体可做保护气，则可做保护气的一定是稀有气体
中和反应生成盐和水，则生成盐和水的反应一定是中和反应
化学学习让我们有了很多收获下列归纳总结完全正确的一组是
A
B
C
D.
归纳和整理是学习化学的有效方法请补全下列有关物质分类的括号图并按题目要求举例
归纳是学习化学常用的方法下列归纳全部正确的是
A
B
C
D
归纳和总结是学习化学的有效方法下列相关知识的归纳总结完全正确的一项是
比较与归纳是我们学习历史的常用方法之一下列有关两次世界大战相似点的归纳不正确的是
德国都是罪魁祸首
美国都从中获利
日本都是战败国
英国都是战胜国
学生在学习了氯气的化学性质后再学习溴的化学性质时常用的逻辑思维方法是
演绎
分类
类比
归纳
归纳是学习化学常用的方法下列归纳全部正确的是
A
B
C
D
推理和归纳是化学学习和研究中常用的思维方法．下列推理不正确的是
归纳总结是化学学习的重要方法下列归纳总结正确的是
A
B
C
D
对已学过的知识进行梳理归纳是中学生应该掌握的学习方法请你完成下列对化学反应的归纳举例写出文字表达式化
归纳总结是化学学习的一种重要方法下列归纳和总结全部正确的一组是
A
B
C
D
归纳总结是化学学习中常用的方法下列归纳总结正确的是
复分解反应中可能同时生成两种沉淀
同种元素组成的物质一定是单质
能使无色酚酞变为红色的物质一定是碱的溶液
有单质和化合物生成的反应一定是置换反应
归纳是学习化学常用的方法．下列归纳全部正确的是
A
B
C
D
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AstudybySanDiegoZooGlobalconservationistsreleasedthisweekSept.122016issheddingnewlightonhowscientistsevaluatepolarbeardietandweightlossduringtheirfasting禁食season.Onaverageapolarbearlosesupto30percentofitstotalbodymass体重whilefastingduringtheopen﹣waterseason.Althoughsomescientistspreviouslybelievedland﹣basedfoodscouldsupplement补充thebears'nutritionalneedsuntiltheseaicereturnsanewstudypublishedinthescientificjournalPhysiologicalandBiochemicalZoologyhasrevealedthataccesstoterrestrialfoodisnotsufficienttoreducetherateofbodymasslossforfastingpolarbears. Thestudy﹣﹣undertakenbyManitobaSustainableDevelopmenttheUniversityofAlbertaandEnvironmentandClimateChangeCanada﹣﹣weighedpolarbearsthatweredetainedinthePolarBearHoldingFacilityinChurchillManitobaCanadafrom2009to2014.PolarbearswerekeptinthisfacilityaspartofthePolarBearAlertProgramwhichaimstoreduceconflictbetweenhumansandpolarbearsaroundthetownofChurchill.Topreventhabituationpolarbearsarenotfedwhileinthefacilitywhichallowedforacontrolledmeasureoftheirweightloss.Onaveragepolarbearslost2.2pounds1kilogramofmassperday﹣﹣exactlythesameamountasfree﹣ranging自由放养的bearsmeasuredduringtheice﹣freeseasononthecoastlineofHudsonBay.Scientistsreportedthatevenwithland﹣basedfoodopportunitiespolarbearslostthesameamountofweight. Somestudieshavesuggestedthatpolarbearscouldadapttoland﹣basedfoodstooffsetthemissingcaloriesduringashortenedhuntingperiodontheicesaidNicholasPilfoldPh.D.leadauthorofthestudyandapostdoctoralassociateinAppliedAnimalEcologyatSanDiegoZooGlobal.Yetourresultscontradictthisasunfedpolarbearsinourstudylostmassatthesamerateasfree﹣rangingbearsthathadaccesstoland﹣basedfood. Researchersalsoestimatedstarvationtimelinesforadultmalesandsubadultsandfoundthatsubadultsweremorelikelytostarvebeforetheiradultcounterparts.SubadultpolarbearshavelowerfatstoresandtheaddedenergydemandsassociatedwithgrowthsaidPilfoldFuturereductionstoon﹣icehuntingopportunitiesduetoseaicelosswillaffecttheyoungerpolarbearsfirst﹣﹣especiallygiventhatthesebearsareless﹣experiencedhunters. 63.Whatisthefindingofthisnewly﹣releasedstudy A.Wildpolarbearsarefacingthedangerofstarvationandextinction. B.Land﹣basedfoodcan'tmeetthenutritionalneedsofwildpolarears. C.Wildpolarbearscanavoidweightlossinaproperlydesignedfacility. D.Traditionalwaystomeasurepolarbeardietandweightlossarenotaccurate. 64.WhichofthefollowingisTRUEaboutthestudy A.ItwasactuallypartofthePolarBearAlertProgram. B.Itaimedtopreventthepolarwildlifefromextinction. C.Itcomparedtheweightlossbetweenunfedandfree﹣rangingpolarbears. D.ltmeasuredtheweightofpolarbearsduringon﹣icehuntingseasons. 65.Theunderlinedwordinthefourthparagraphmeans. A.takeover B.takeup C.makeinto D.makeupfor 66.Thereasonswhysubadultsaremorelikelytosufferduringopen﹣waterseasoninclude. Theyhavelessfatstorage. Theyneedmoreenergyforgrowth. Theylackhuntingopportunities. Theyareslowerinadaptingtoiceloss. A.①②B.③④C.①②③D.②③④
如图圆柱形盛水容器横截面积为S1．重力为G的柱形金属块横截面积为S2已知S1＞S2金属块用细线悬挂并使之底面恰好与水面齐平．现将金属块缓慢下降浸入水中设水均不溢出且金属块不浸没水的密度为ρ则 1金属块底面在水中深度为h时金属块所受浮力为多少 2金属块相对容器底部下降高度为H时盛水容器底部增大的压强是多少
随着物联网技术的发展智能家居已悄然走向前台．下图为智能家居中的安防系统和饮用水净化系统请回答问题 1安防系统 门禁系统智能家居的门禁系统倾向于利用生物识别如指纹锁等．不同的人指纹不同指纹是人的一种性状由决定．烟雾报警图1是烟雾报警器的简化原理图其中电源电压恒定不变R0为定值电阻R为光敏电阻当有烟雾遮挡射向光敏电阻的激光时电路中的电流减小到某一数值时报警器开始报警．则光敏电阻的阻值随光照强度的减弱而选填“增大”“减小”或“不变”此时电压表示数较未报警前选填 “增大”“减小”或“不变”． 2饮用水净化系统 如图2所示在饮用水净化系统中设备①②③的作用分别是．
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Agrouptripismuchmoredifferentthanwhatonemightexpectwithanorganizedtourorasoloholiday.1Thusitiscertainlyanexperiencetoenjoy. Goingonholidaywithagroupoffriendsisallabouthavingfuncreatingmemoriesandtryinganewexperiencewithasharedinteresttotravel.2Italsohelpsyoulearnmoreabouthowtotravel.Whetheryoudecidetogoinalargegroupofupto10peopleormoreorgoinamuchsmallergroupof4grouptripsareagreatwaytobondandreconnectwithoneanother.3Itcanhappenperiodicallyperhapsonceortwiceayear. Planningagrouptripmaybedifficultbuttheresultwillbesatisfying.Chooseapopularlyknowndestinationoranunknowndestination.Thisdecisioncanactuallysetthefoundationforthemoodofthetrip.4Thiswillgivegroupmembersanideaofwhattheycanexpectforthenextgrouptrip. Thepurposeofthegrouptripforsomemaybetoescapefromthecityortheircurrentbusyschedules.5Whethertheywillbepositiveornegativememoriesthemainideaisthatasagrouptheywillbeabletolinktheirtriptothememoriescreated. A.Besidesitdoesn'thavetobeaconstantactivity. B.Youwillonlyenjoysuchatriponceinalifetime. C.Itmeansbeinginsidejokesgreatstoriesandplentyoflaughs. D.It'sspecialbothinitsformandtheuniqueexperienceitoffers. E.Forothersitmaybetocatchupwithfriendsoveraperiodoftime. F.Theyhavebeenalonefortoolongatimeandthusbadlyneedatrip. G.Youwillexperienceneworfamiliardestimationswithcloseacquaintances.
下列关于四种粒子的结构示意图的说法中不正确的是
某工厂化验室用稀盐酸测定造纸厂废水中氢氧化钠的质量分数取废水样品100g倒入烧杯中逐滴加入9.8%的稀硫酸至恰好完全反应共用去稀硫酸50g请计算 温馨提示H2SO4+2NaOH＝Na2SO4+2H2O 1中和废水所用硫酸的质量 2废水中氢氧化钠的质量分数．
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Onetrendinappdevelopmentispositivityprogramsdesignedspecificallytohelpretrainourbraintothinkpositively.Hereareourtoprecommendationsforappstoimproveyourpositivemood. ThinkUp Havinga4.7starratingthisappisaheavyhitterintheworldofpositivityapps. Peoplearefindingthattheycanlearntobepositiveandsavetheirlivesfromtheconvenienceoftheirhandhelddevices设备.Wenolongerhavetogotothelibraryandcheckoutbooks.Justdownloadthisfreeappandstartthinkingpositivelyandwatchhowyourlifechanges. Shine Thisappisrecognizedasthebestof2018andithelpsyouwithdailymotivationandpersonalcare.Thisapp'sgoalistohelpreduceyourstresssodon'tworryaboutaddingonemorethingtoyourto﹣dolist.Theysendmotivationaltextsincludingagratitudejournal.Thisisanincrediblewaytechnologyjoinsgreatmindssowecanallimprovetogether! Happler Holdingastrong3.9starevaluationgradethisisonewelove.Itcanhelpyoukeepajournalhasincrediblecoursesandletsyouexchangeideaswithawholecommunityofpeopleworkingtobecomemorepositive.Welovethecreativitythatwentintomakingthisappandthinkithasalottooffer. Motivate Thisappgainsa4.8starratingafterover2622ratingswhichhashandpickedmotivationvideosandmusicplaylistsforanymoodyou'dliketogetinto.Ifyouneedtorelaxorgetenergizedorinspiredtogrowinspecificareasofyourlifethisuniqueappwillhelpyouchooseyourcategoryandgetyouthinkingpositivelyaboutitthroughtheuseofimagesandmusic. 1Whichcanhelpyouwithpersonalcare? A.ThinkUp. B.Shine. C.Happier. D.Motivate. 2Whatdothefourappshaveincommon? A.Theyofferinteractiveteaching. B.Theyenableuserstobemorepositive. C.Theyareallstar﹣rated. D.Theyhelppeoplereachtheirgoals. 3What'sspecialabouttheappMotivate? A.Itgainsthehighestrating. B.Ithelpspeoplekeepajournal. C.Itprovidesvideosandmusic. D.Itsendsmotivationaltexts.
“钢玉”又名红宝石其主要成分是“SiO2”其中硅元素“Si”的化合价是
现有XYZ三种金属已知①X和稀硫酸不反应②Z+H2SO4稀═ZSO4+H2↑③X+2YNO3═2Y+XNO32这三种金属的活动性顺序正确的是
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如图是MN两种固体物质的溶解度曲线．下列说法不正确的是
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将一种金属M投入AgNO3和CuNO32的混合溶液中充分反应后溶液变为无色．过滤得到滤渣和滤液． 1根据所学知识及上述现象判断MAgCu三种金属的活动性由强到弱的顺序是． 2下列说法正确的是填序号 a．M可能是Feb．滤液中滴入稀盐酸可能产生白色沉淀 c．滤渣中滴入稀盐酸一定有气泡产生d．滤渣中一定有Ag和Cu可能有M．
写出符号“3O2﹣”中数字的含义 “3”表示 “2”表示．
Chinesedragons龙arefictionalcreaturesarootofChinesepeoplewhoconsideredthemselvesasthedescendants后代ofdragons.SincetheircreationChinesedragons1winthedeeplovefromChinesepeoplebecauseof2theystrongpowerandsymbolicmeanings.Theyplayed3importantroleinthehistoryofChinesenationpoliticsreligioncultureandChineselanguageandbecameasymbolofChinaandChinesepeople. DragonisabeliefofChinesenationanda4goldChineseelement元素.WhenapersonhearsthenameofdragonChina5cometohisorhermind.Asthestrongestanimal6selectbyChinesepeopledragonhasthestrongestpower7helpsitgototheHeavenandtheHellandmakecloudandrains.Inancienttimesasabeliefdragongavestrongsupportstotherulingofabignationandtopeople'sfragilespiritsandhardlifebecausepeoplesufferedfromextremenaturaldisastersandlack8thesupportsfromscience.The9importantofdragontoChinesepeopleislikewatertocreaturesandit10reflectinpeople'sspiritbeliefsandideology.
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小乐利用长宽和厚度均相同的锌片铁片与铜片完成了以下实验 利用锌片和铜片制作电池 1小乐从课本中得知将一块锌片和一块铜片插入稀硫酸就可以组成一个电池铜片和锌片是电池的两个电极且溶液中部分离子移动的方向和电极上电子移动的方向如图乙所示．此电池的能量转化是若要用电压表测此电池的电压则电压表的负接线柱应与相连选填“铜片”或“锌片” 2小乐从课本中还知道若在水果中插入锌片和铜片可以制得水果电池于是她完成了 如下实验 通过上述实验可知水果电池电压大小的影响因素有．
水是生命之源我们应该了解水爱护水资源请回答 1生活中的自来水属于填“纯净物”或“混合物”． 2使用硬水会带来许多麻烦日常生活中可用检验硬水和软水通过的方法既能降低水的硬度又能杀灭部分细菌．自来水厂的净水过程中常利用活性炭的性除去水中的异味和色素． 3如图为电解水的实验装置图．接通电源观察到两电极都有气泡产生．通电一段时间后ab两玻璃管收集的气体体积比约为该实验证明了水是由组成的． 4二氧化氯是新一代饮用水的消毒剂我国成功研制出制取二氧化氯的新方法其反应的原理是通过氯气Cl2与亚氯酸钠NaClO2反应生成二氧化氯气体和氯化钠．请写出反应的化学方程式．
如图所示倾斜装置使液体和固体混合气球体积没有明显变化的是
A.changingB.availableC.exposureD.worsenE.sensitive F.densityG.restH.shadedI.refleciionsJ.interruptedK.fighting Areyoureyesdrywateryseeingdoubleor31tolightanddoyourbackandneckacheIfsoyouarelikelyoneofmanypeopletodaywhosufferfromdigitaleyestrain视疲劳alsocalledcomputer﹣visionsyndrome. Eyestrainisoftenrelatedtotheamountof32toscreensthedistancefromeyestoscreensandtheuseofmultiplescreensatthesametime.Howeverstudies havealsoshownthatthebluelightproducedbydigitaldevicesreachesfurtherintotheeyesthanotherkindsoflight.Thislightactuallyassisisattentionduringthedaybutcanresultin33sleeppatternsatnight. Scientistshavestatedthateyestrainisnotanecessaryevileveninamodernworldthatcirclesaroundtechnology.Sometimes34somesimpledetailsaboutyourrelativepositiontoscreenssuchasslayingabout60centimetersawaywillhelp.Alsoavoidoverheadandotherdirectsourcesoflightanduse35lampsandwindowblindswhilelookingatdigitaldevicesinstead. Beyondthewaysthatyourelatetodigitalscreenstherearealsowaystochangehowyouviewscreensthatarehelpfulin36eyestrain.Tobeginwithyourcomputerscreenshouldbehigh﹣resolution高分辨率andmayrequireascreentodecrease37.Alsobeawarethat''computerglasseswhichcutdownglare刺眼的光}andbluelightare38onthemarkect. Finallymanyofusfallintobadhabitswhileusiugdigitalscreensthatonly39theeffectsofeyestrain.Whenviewingdigitalscreensmanypeopleblink眨眼onethirdlessoftenthantheyusuallydo.Placeareminderonyourcomputertoblink!sothatyoureyesdon'tdryout.Also40youreyes'focusingmusclesbyusingthe20﹣20﹣20ruleevery20minutesfocusonsomething20feetawayfor20seconds. Therearemanyothermethodsusedtohelprelieveeyestrainsofindwhatworksforyouratherthangivingintotiredvision.
在元素周期表中镁元素的信息如图所示下列有关说法不正确的是
WiththeaveragenumberofchildreninaBritishfamilyfallingunderanaverageof2.0comparedwiththetraditional2.4childrenthepopulationoftheUKhasbeenfallingforquiteafewyears. Whyaren'tBritishpeoplehavingasmanychildrenastheyusedtoWelltherearemanyreasons.OneofthemisthatBritishpeoplearenowhavingtheirchildrenatamucholderagethanpreviouslymeaningtheyhavefeweryearsinwhichtheycanhavechildren.Mostyoungpeopletodaywantawell﹣paidjobsotheyoftengotouniversityafterhighschoolafteryearsofstudyatuniversitytheythenneedafewyearsofworkexperiencebeforetheycangetthejobtheywant.Soit'snotuntiltheyareabout30yearsoldthattheycanstarttothinkaboutsettlingdownandhavingchildren. AnotherreasonisthatitisrelativelyexpensivetobringupachildintheUK.Usuallybothparentsneedtoworktopayfortheirhomeandlivingexpenses.Theyneedtopaysomeonetolookaftertheirchildduringthedaywhichisexpensive. InadditionproblemsintheglobaleconomyoftenaffectBritishfamilies.Forexamplewhentimesaretoughandthereisaneconomicdownturnitbecomesdifficulttofindajoborkeeptheexistingone.Thiskindofuncertaintydiscouragespeoplefromhavinglargerfamilies. SowhatisBritaindoingtotryandsaveBritishfamiliesFirstofallthegovermmentistryingtomakeitcheapertohavechildren.Forexampletherehavebeenincreasesinmoneyfamiliescangainfromthestateeachmonth.Alsothereisanincreasingamountofmoneyfornurseryschoolssothatparentsdon'tneedtopaysomuchforchildcare.Inadditiontherearenowlawsallowingparentstotakemoretimeoffworksothattheycanlookaftertheirchildrenthemselvesratherthanhavingtopayotherstodoit. .
空气中含量较多且性质活泼的气体是
化学是一门以实验为基础的科学．请结合图示回答问题 1写出仪器a的名称． 2实验室用氯酸钾和二氧化锰制取氧气反应的化学方程式为应选择的发生装置是填字母．用E装置收集氧气若氧气不纯可能的原因是． 3雨欣同学选用图1中的填字母装置制取二氧化碳并与图2装置连接验证二氧化碳能与水反应生成一种酸性物质．F的作用是除去氯化氢气体G中的试剂是．当通入二氧化碳一段时间后H中纸花I中的纸花．
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