化学专业英语写作-第四章.ppt

1,第四章有关数理化内容的表达,2,4.1有关数学内容的表达用语,4.1.1有关普通数的表达普通数的基本写法1.一般原则(1)10及10以上的数字写成阿拉伯数字(2)10以下的它拼写出来，如3写成three，但若10以下的数字后面带有单位，则仍写成阿拉伯数字，如6inches,3Cubicyards.,3,(3)从21至99间的数在书写时，十位与个数之间加连字写，如21应写成twenty-one(4)当数字频繁出现时则仍写成阿拉伯数字。Heusedacrewof3carpenters,2plumber,6laborers,1foreman,and1timekeeper.(5)在同一短语中出现两个相邻数字时，其中一个拼写出来，一个写成阿拉伯数字，一般是将小的拼写出来，较大的写成阿拉伯数字。7six-inchtimber梁木fifteen40-wattlamps,4,(6)仅作为估计数的数字一般都写出来这幢大楼应能使用50年Thebuildingshouldstandforfiftyyears.(7)金额总和一般以阿拉伯数字表示15dollars或$150.8080cents但有时必需拼写出来，如写支票取款时，fivehundredandfifty-sixpounds,556(8)一般来说一个句子不要以阿拉伯数字开始，遇到这种情况，应将数字拼写出来或采用一般变通办法。,5,2.具体写法(1)整数三位数以内没有特殊要求四位数时有两种写法，1234或1,234超过四位数时，每向左增加三位加一逗号；168,230milespersec.(2)小数，前面多带0。如0.52(3)文字和数字有连字号组成时一位数时多用文字拼写表达four-wirecircuit二位数时用拼写或阿拉伯数字表示均可60-ChannelSystem或Sixty-ChannelSystem三位数三位数以上均用阿拉伯数字表示60,000-houroperatinglife,6,有关确切数的表达个位数unitsdigit(s),十位数tensdigit(s)百位数hundredsdigit(s)三位数threedigits,threefigures多位数multidigitnumber三位有效数threesignificantfigures总数为aatotalofa总数不为aatotaldifferentfroma或atotalotherthana总数至多为aatotalatmosta总数至少为aatotalatleasta,7,至多2个9atmost2ninesn个中之一oneofn28或少于2828orless30或多于3030ormore多于100少于1000morethan100butlessthan1,000五中取二twooutoffive百分之一ahundredthpartof千分之三athirdpartin1000百万分之五5partsinamillion,5partin1061,23E0,123E-20123E2oneandtwentythreeonehundredths,8,4.1.3约数的表达一、约数：汉语中的“大约”、“左右”、“上下”英语中可以用下面方式表达1.词(组)+基数词about+基数词about80to100milesaround+基数词around1991some+基数词some40tonesinweightnearly+基数词nearly10,000peopleapproximately+基数词approximately50hoursmoreorless+基数词moreorless50metersalmost+基数词almost300visitors,9,2.基数词(可跟单位)+词组基数词+orso50metersorso基数词+upanddown10nmupanddown基数词+moreorless30kmmoreorless基数词+thereabout15thereabout,10,二、多于的表达1.词组+基数词(可跟单位)above+基数词above25inexcessof+基数词inexcessof220squaremilesover+基数词over3000upwardsof+基数词upwardsof800gwater2.基数词+词组基数词+oddthirtyoddyears基数词+andmore(over)fortyandmore,11,三、少于的表达below+基数词below980lessthan+基数词lessthan3000under+基数词under11ms,12,不确定量的表达十之八九tentoone,nineinten许多scoresof,alotsof,alargenumberof,plentyof,amultitudeof许许多多twentyandtwenty,aworldof0至9fromzerothroughnine二十多twentyandodd几十afewtens几百hundredsof,somehundredsof几千thousandsof,somethousandsof,13,几万tensofthousandsof大约3万some30,000几十万hundredsofthousandsof几百万millionsof几亿hundredsofmillions千百万millionsuponmillionsof数周(天,时,)acoupleofweeks(days,hours)零上几度afewdegreesabovezero,14,平均值以上aboveaverage海拔1000米以上1000metersabovesea-level约在50至500之内between50and500约109中的一个原子latominabout109零点几伏afewtenthofavolt250毫秒上下250msupanddown五十打以上50dozenorup(move)超额百分之三以上anyexcessover3percent注意：over,above虽都表示“以上”的意思，但over多用于表示数量和长度的内容，表示高低或以刻度的内容时多用above。,15,4.1.5含有外来语词头的数字1.monomonochrone单色的monoxideuniunidirectional单向的2.didiatomic双原子diphase二相的bibimonthly双月的bidentate双齿的3.tritriangle三角形的4.tetratetragon四边形的quadrquadraphonics四声道立体声5.pentapentagon五角形pentagram五角quinquequinquevalence五价的,16,6.hexahexagon六角形7.heptaheptode七极管8.octoctane辛烷octhedron八面体octachord八弦琴octacosane二十八烷octadecanol十八烷醇9.nonanonane壬烷nonamer九聚物10.decadecane癸烷，十碳烷多polypolygon多边形multimulticolored多色的全omniomnidirectional全向的半hemihemicycle半圆的semisemiperiod半周期demidemicontinuous半连续的demilume半月,17,含有“半”意的数字表达(1)单独使用时用halfhalfayear,halfanhour,ahalfhour(2)与其它数字搭配使用时andahalfthreeyearsandahalffivedaysandahalfsixtonsandahalf六吨半sevenkilometersandahalf(3)作为词头使用时用halfhalfhourly每半小时halfadder半加器halfangle半角halflife半衰期,18,罗马字的表达145678910111920大数罗马字还有：501005001,000LCDM字数上加“”表示扩大1000倍V5000,L50000其它数字可由基本数字组合而成CCDLMD2035501512,19,数量级的表达用语有oftheorderof,ontheorderof,intheorderof,oftheorderof,magnitudeof来表示Gatecurrentsarenormallyoftheorderofpicoamperes.Thefrictionalforceisvelocitydependent,butattypicalspeedstheeffectivecoefficientoffrictionisoftheorderof0.001.,20,数量增减的表达(1)高(快，低)达的表达as+形容词+as+数词低达Successfuloperationofthesedevicesrequiresairpressuresaslowas108mmofmercury.高达，快达atspeedashighas1800revmin1,21,(2)净增(减)的表达下降6%，增加6%Weknowthatfrom1990to1991thenetincomeofthecompanydeclinedby6%,whereasfrom1991to1992thenetincomeincreasesby6%.相差10%Thesetwomeasurementsdifferby10%.,22,(3)倍数增大的表达a.净增倍数的表达增加意义的谓语+by+数字提高7.5Thesignallevelhastobeincreasedby7.5.b.为的x倍xtimes+名词或thatof约是的三倍Themeltingpointofaluminumisaboutthreetimesthatoflead.c.比重(大)x倍x+比较级+than几乎比重三倍Ironisalmostthreetimesheavierthanaluminum.,23,d.为x倍大(快、高)x+as+形容词+asThespeedofsoundinwaterisaboutfourtimesasgreatasinair.e.增至x倍或增加x1倍增加意义谓语+byafactorofx增到11.7倍Ifadonor-typeimpurityisaddedtotheextentof1partin108,theconductivityofgermaniumat30ismultipliedbyafactorof11.7.,24,增加意义谓语+数字+timesThesalesofmicrocomputerhasincreasedsixtimessince1970.用double(treble)等谓语Ifwetreblethepressure.倍数减少的表达减少到1/5(减少了4/5)isreducedbyafactorof5减少为1/4isreducedfourtimes使用fold放在基数词的后面Theexecutivetimeisalsoincreased,sometimesseveral-fold.,25,4.2物理量的变化表达,4.2.1物理量自身变化的表达增减或变化的名词+in+物理量电压增大increaseinvoltage温度升高riseintemperature温度变化variationintemperature体积减少decreaseinvolume动能的改变changeinkineticenergy液体上升elevationinfluid,26,在加压下固体的体积变化十分小，以致方程1中的体积V可认为是一个常数。ThechangeinvolumeofasolidunderpressureissosmallthatthevolumeVineq.1canbeconsideredconstant.材料的压缩系数等于每增加一个单位压力时的相对体积的减少Thecompressibilityofamaterialequalsthefractionaldecreaseinvolumeperunitincreaseinpressure.,27,4.2.2物理量随其它因素变化的表达一般表达式为changewith,varywith在大气层上部，气温仅随高度略有变化.Intheupperpartoftheatmospherethetemperaturevariesonlyslightlywithchangeinelevation.体积随压力反变化Thevolumevariesinverselywithpressure.,28,dQ在dt时间内的增加比例于图1中的深色阴影区。TheincreaseindQinthetimedtisproportionaltotheheavilyshadedareainFig.1.在0至4，水的体积随温度升高而减小Water,inthetemperaturerangefrom0to4,decreasesinvolumewithincreasingtemperature.,29,4.2.3几何尺寸和形状的表达长度、高度和厚度直径12毫米的钢球asteelball1to2mmindiameter直径2毫米的钢球asteelballof2mmindiameter10厘米长的铜棒acopperrod10cmlong薄到2的纤维afiberasthinas2宽度各为0.1mm的平行槽parallelslitseachofwidth0.1mm,30,90厘米长的玻璃管aglasstube90cmlong厚度为0.5cm的黄铜板abrassplate0.5cmthick长12ft直径0.036inch的铜线acopperwire12ftlongand0.036inchindiameter安装在16英寸宽，41/4英寸高，111/2英寸深的框架中bemountedina16incheswide,41/4inchesheightand111/2inchesdeepframe.,31,面积和体积容量20立方米的容器atankhavingacapacityof20m3容量2l的烧瓶aflaskofvolume2l235cm3的钢锭235cm3steelblock或atwobythreebyfivecm3steelblock直径2102毫升长1毫米的毛细管acapillaryofdiameter2102mmandlength1mm.,32,宽5厘米长18厘米的长方薄板arectangularsheet5cmwideand12cmlong六股七丝的电缆sixbysevencable一间4米5米的房间aroom4mby5m在2个大气压下温度为27时的一升氦aliterofheliumunderapressureof2atmandatatemperatureof27,33,形状的表达1.按汉字形状表达丁字形螺栓Tbolt丁字形槽Tslot丁字形钢Tsteel工字钢I-steel十字管Cross-pipe元字形Zigzag人字架A-bracket,34,2.按英语字母形状表达Z形梁ZbeamV形齿轮VgearS形曲线SshapedcurveO形环OringU形管UtubeA形架AframeT形刀架Trest,35,3.按实物形状表达菱形diamond-shape上凹的concaveupward星形star-like下凹的concavedownward锲形Vshape上凸的convexupward槽钢Usteel椭圆形oval8字形afigure-of-eight双凸面convexo-convex阶梯形staircase亚铃形dumbbell-shaped,36,4.2.4精度的表达可读到1/10刻度canbereadto1/10division样品夹持器可对准中心到0.002毫米的范围内.Thesampleholdercancenteredwithin0.002ofamillimeter.所有测量只记录适量的有效位.Allmeasurementsshouldberecordedonlytotheappropriatenumberofsignificantfigures.准确到两位beaccuratetotwodecimalplaces记录到一位数的精度berecordedtoone-decimalaccuracy被舍入至最近的分数值beroundedtothenearestfractionalvalue,37,4.2.5角度的表示与电子运动方向成角beatanangletothedirectionofmotionoftheelectronA与B在相隔3的方向上AandBareindirectionseparatedby3与x轴成倾斜beobliquewithrespecttox-axis置M与Z轴垂直MisplacedperpendiculartotheZ-axisSP2hybridizationisindicatedwheneveranatomformsthreeidenticalbonddirectedat120toeachother.C2H4moleculeisalsoflat,andthebondsfromeachCarbonatommakeverynearly120witheachother.ThetwoH-Obondsinwatermoleculemakeanangleof105witheachother.,38,4.2.6温度和湿度的表达在1000K以上(附近，以下)的温度attemperatureabove(around,below)1000K80的500克水500gofwateratatemperatureof80在常温下atordinarytemperature在室温下atroomtemperature在三态点atthetriplepoint在临界温度点以上的气体agasatatemperatureabovethecriticalpoint在相对湿度为100%时at100%relativehumidity,39,4.2.7压力的表达压力在106Torr以上(以下，附近)atpressureabove(below,around)106Torr1.02105压力apressureof1.02105Pa在低于0.13帕的真空下underavacuumoflessthan0.13Pa,40,4.2.8位置，方位关系的表达1.地理位置，需要借助介词in,to,on等(1)in用于某地属于某一范围之内的情况中国在亚洲东部ChinaisintheeastofAsia.(2)to用于某地不属于某一范围的情况朝鲜位于日本以西KorealiestothewestofJapan.(3)on仅表示位置中国东临太平洋ChinafacesPacificontheeast.(4)of表示与某地之距离有方位关系他的祖籍在上海以北100英里处.Hisnativeprovinceis100mile(tothe)northofShanghai.,41,A市位于Z市上游1500英里处.CityAislocatedsome1500milesupriverfromcityZ.A市位于C省，在X河南岸，距海约380英里CityAislocatedinCProvince,onthesouthbandoftheXRiver,about80milesfromthesea.A市位于B省内X河与Y河交汇处，在K上游669英里.CityAissituatedinBProvinceatthejunctionofXandYRivers,some699milesupriverfromK.,42,2.方位关系方位(compasspoints)表达，东西两个方向英汉表达顺序一致，而南北两个方向语序相反。东南Southeast(SE)东偏北Eastbynorth东北Northeast(NE)西偏北Westbynorth西南Southwest(SW)南偏西Southbywest西北Northwest(NW)北偏东Northbyeast,43,4.3化学常用表达用语4.3.1NomenclatureofCompoundsNomenclatureofInorganicCompounds,44,一、Namingioniccompounds1.positiveions(1)Monatomiccationshavingsingleoxidationnumberstakenameofthemetalfromwhichtheyarederived.Forexample,Na+isnamedsodium;Mg2+isnamedmagnesium,Al3+isnamedaluminum,andsoon.,45,(2)Monatomiccationshavingmultipleoxidationnumbersarenamedineitheroftwoways:(a)TheiontakestheEnglishnameofthemetalfromwhichitisderived,immediatelyfollowedbyaRomannumeralwritteninparenthesisthatindicatestheoxidationnumber.ThissystemofnamingioniccompoundsiscalledtheStockSystem.Forexample,Cu+isnamedCopper()andCu2+isnamedCopper();Fe2+isnamediron()andFe3+isnamediron()Sn2+isnamedtin()andSn4+isnamedtin();andsoon.,46,(b)TheiontakestheLatinnameofthemetalfromwhichitisderivedtogetherwithoneofthesuffixes-ousor-ic,representingthelowerandhigheroxidationnumbers.Weshallcallthissystemofnamingioniccompoundstheoldersystem.Forexample,Cu+isnamedcuprousandCu2+isnamedcupric;Fe2+isnamedferrousandFe3+isnamedferric;Sn2+isnamedstannousandSn4+isnamedstannic;andsoon.,47,(3)Thereareonlytwocommonpolyatomiccations,Theirformulasandnamesarenotedbelow:NH4+ammoniumHg22+Mercury(I)inthestockSystemMercurousintheolderSystem2.Negativeions(1)Monatomicanionsarenamedbyaddingthesuffix-idetothestemofthenameofthenonmetalfromwhichtheyarederived.Forexample,HOisnamedhydride.Clisnamedchroride,O2oxide,N3nitrideandsoon.,48,(2)polyatomicanionsarenamedaccordingtothefollowingsystem:(a)Thebinaryanionsarenamedwiththesuffix-ide;OHhydroxideCNcyanide.(b)Thepolyatomicanionscontainingcarbonarenameduniquely;C2H3O2acetateCO32carbonateC2O42oxalate,49,(c)whenanonmetalformstwodifferentoxyanions(anionscontainingoxygen),thesuffix-iteisusedtonamecontainingthenonmetalwiththelesseroxidationnumberandsuffix-ateisusedtohigherNO2nitrite,NO3nitrateSO3sulfite,SO22sulfate,50,(d)whenanonmetalformsmorethantwodifferentoxyanions,theprefixeshypo-(meaninglowerthanusual)andper(meaninghighthanusual)areusedtogetherwiththesuffixes,-iteand-ate,inorderofincreasingoxidationnumber,asfellows:hypo-ite,-ite,-ate,andper-ate.PO2hypophosphitePO3phosphitePO43phosphateClOhypochloriteClO2chloriteClO3chlorateClO4perchlorate,51,(e)oxyanionscontaininghydrogen(exceptacetateandhydroxide)arenamedhydrogen()oralternatively,bi()HCO3hydrogencarbonate,orbicarbonateHSO3hydrogensulfite,orbisulfiteHSO4hydrogensulfate,orbisulfate例.Na2C2O4sodiumoxalate,HgSO4Mercury()sulfateorMercuricsulfate,Fe3(PO4)2iron()phosphate,ferrousphosphate,Ca(HCO3)2calciumbicarbonate.,52,二Namingbinarycovalentcompounds.Firstwenametheelementthatiswrittenfirstinthechemicalformula,precededbyaGreakprefixthattellushowmanyatomsoftheelementareinthecompound;thenwenametheotherelement,precedingitbyanotherGreekprefixthattellsushowmanyatomsofthissecondelementareinthecompound.Greekprefix+firstelement+Greekprefix+anotherelement+(endsin-ide)withpositiveoxidationnumberiswrittenfirst.Eachoftheseelementsisanonmetal,orametalloid,andthenameofthesecondoneismodifiedsothatitendin,53,-ide.Theelementwiththepositiveoxidationnumberiswrittenandnamedfirst.Hencethesymboloftheelementthatappearsearliestinthefollowingsequenceiswrittenfirst:B,Si,C,Sb,As,P,N,H,S,I,Br,Cl,O,F,Agreatmanybinarycovalentcompoundshaveacquiredcommonnamesthatareusedmorefrequentlythanthesederivedfromthesystematicprocedurenotedabove.Insomecasesthesenamesareexclusivelyused.,54,GreekprefixnumberExampleMono-1CarbonmonoxideCODi-2CarbondioxideCO2Tri-3PhosphorustrichloridePCl3Tetra-4CarbontetrachlorideCCl4Penta-5PhosphoruspentachloridePCl5Hexa-6SulfurhexafluorideSF6Hepta-7DichlorineheptoxideCl2O7Octa-8DichlorineoctoxideCl2O8Ennea-或(nona)9TetraiodineenneaoxideI4O9Deca-10TetraphosphorusdecoxideP4O10,55,*whentwovowelsappearnexttooneanother,asinmonooxideandaoinheptaoxide,thevowelfromtheGreekprefixisdroppedforthesakeofeuphony.Acceptablenamesforsamecommonbinarycovalentcompounds.NH3ammoniaAsH3arsineN2H4hydrazineH2ShydrogensulfideCH4methanePH3phosphineSiH4silaneH2Owater,56,三NamingacidsBinaryacidscontainhydrogenandoneothernonmetal.ThegeneralchemicalformulaofbinaryacidisHXorH2X,whereXisaparticularnonmetal.Theyarenamedbyplacingtheprefixhydro-beforethestemofthenameoftheidentifyingnonmetal,andattachingthesuffixictothestemofthenonmetal,followedbythewordacid.Thismeansthatthebinaryacidsarenamedasfollows:hydro-(stemofthenonmetal)-ic.Acid.,57,Forexample,considerthenamesofthefollowingbinaryacids:HFhydrofluoricacidHClhydrochloricacidH2ShydrosulfuricacidHCNisnamedhydrocyanicacid,Eventhoughitisntbinary.Oxyacidsareacidsthatcontainoneormoreoxygenatomsinadditiontooneormorehydrogenatomsandtheidentifyingnonmetal.ThegeneralformulaofanoxyacidisHmXOn.TheidentifyingnonmetalXmayexistwithdifferentoxidationnumbers,andtheremaybeanacidthatcorrespondstoeachnumber.,58,Thevariousoxidationnumbers(ON)aredifferentiatedinthenamesoftheoxyacidsbytheuseoftheprefixeshypo-andper-,andbythesuffixes,-ousandic,accordingtothefollowingrules:1.Iftheidentifyingnonmetal(I.N)hasonlyoneON,thesuffix-icisusedafterthestemofthenonmetal.,59,2.IftheI.N.hastwoON.ThesuffixousisusedafterthestemofthenonmetalpossessingthelowerON,andthesuffixicisusedofthestemofthenonmetalpossessingthehigherON.3.IftheINhasmultipleoxidationnumbers,theprefixhypo-andthesuffixousareusedwiththestemofthenonmetalpossessinganevenlowerONthanfoundintheacidnamedwithoussuffix;theprefixper-andthesuffixicareusedwiththestemofnonmetalpossessinganevenhigherONthanfoundintheacidnamedwiththeicsuffix.,60,numberofO.NPrefix/SuffixExampleO.NofidentifyingnonmetalOneicboricacidH3BO3+3Two-ousSulfurousacidH2SO3+4NitrousacidHNO2+3-icSulfuricacidH2SO4+6NitricacidHNO3+5ThreeHypo-ousHypophosphorousacidH3PO2+1-ousPhosphorousacidH3PO3+3-icPhosphoricacidH3PO4+5FourHypo-ousHypochlorousacidHClO+1-ousChlorousacidHClO2+3-icChloricacidHClO3+5Per-icPerchloricacidHClO4+7,61,H4P2O7diphosphoricorpyrophosphoricacidH5P3O10triphosphoricacidH2S2O3thiosulfuricacidH2S2O7disulfuricacidH2S2O6dithionicacidH2SO5PeroxomonosulfuricacidH2S2O4dithionousacidH2S2O8peroxodisulfuricacid,62,四Namingacoordinationcompounds(1)orderofthelistingionsThecationisnamedfirstandthentheanion.(2)NamesofLigandsNeutralligandsarenamedasthemolecule,negativeligandsendino;andpositiveligandsendiniumNH2CH2CH2NH2ethylenediamine(C6H5)3Ptriphenylphosphine,63,ClchloroCH3COOacetatoNH2NH3+hydraziniumTwoexceptionstothisrulearewaterandmoniaH2OaquoNH3ammine(Notethespellingwithtwoms;thisappliesonlytoNH3;otheraminesarespelledwiththeusualonem),64,(3)orderoftheligandTheligandsinacomplexarenamedintheorder(a)negative(b)neutral,and(c)positive,withoutseparationbyhyphens.Withineachofthesecategoriesthegroupsarelistedinorderofincreasingcomplexity.(4)TerminationofnamesTheendingforanioniccomplexesisate;alternatively,-icifnamedasanacid.,65,(5)oxidationstatesTheoxidationstateofthecentralatomisdesignatedbyaRomannumeralinparenthesisattheendofthenameofthecomplex,withoutaspacebetweenthetwo.ForexamplePt(NH3)4(NO2)ClSO4chloronitrotetraammineplatinum(IV)sulfateNH4Cr(NH3)2(NCS)4ammoniumtetrathiocyanatodiamminechromate()Ca2Fe(CN)6Calciumhexacyanoferrate()Fe(H2O)6SO4hexaaquoiron()sulfate.,66,(6)BridgingGroupsligandthatbridgetwocentersofcoordinationareprecededbytheGreekLetter,whichisrepeatedbeforethenameofeachdifferentkindofbridginggroupoctaammine-amido-nitrodicobalt()nitrate硝酸八氨-氨基-硝基合二钴(),67,(7)pointofattachmentWhennecessary,thepointofattachmentofaligandisdesignatedbyplacingthesymbol(initalics)oftheelementattachedafterthenameofthegroup,withseparationbyhyphen.(NH4)3Cr(NCS)6ammoniumhexathiocyanato-N-chromate()(NH4)2pt(SCN6)ammoniumhexathiocyanato-S-platinate()Forthiocyanateandnitriteionsthefollowingoptionalnamesmaybeused-SCNthiocyanato-NO2nitro-NCSisothiocyanate-ONOnitrito,68,(8)Geometricalisomerstrans-cis-(9)opticalisomersDextro-andLevorotatorycompoundsarerespectivelydesignatedEitherby(+)or()orbydorl(+),ord-K3Ir(C2O4)3potassium(+),ord-trioxalatoiridate(),69,NomenclatureoforganiccompoundsAlkanesThenamesforthefirstthirtycontinuous-chainalkanesarelistedinTableA1.BranchedAlkanesInnaminganalkanewithalkylsubstituents,thelongestcontinuouschainisconsideredtheparent.Theparentisnumberedfromoneendtotheother,thedirectionbeingchosentogivethelowestnumberstothesubstituents.Theentirenameofthestructureisthencomposedof(1)thenumbersofthepositionsofthesubstituents;(2)thenamesofthesubstituents;and(3)thenameoftheparent.,70,AlkylSubstituentsThenamesofthealkylsubstituents(alsocalledbranches,orradicals)arederivedfromthenamesoftheircorrespondingalkaneswiththeendingchangedfromanetoyl.Forexample,CH3CH2isethyl(fromethane).Multiplesubstituentsareplacedinalphabeticalorder,eachprecededbyitsrespectivenumberandlikesubstituentsgroupedtogethersomecommonbranchedalkylsubstituentshavetrivialnames(seeTableA2).,71,TableA1molecularNamemolecularnameformulaformulaCH4MethaneC2H6EthaneC3H8PropaneC4H10ButaneC5H12PentaneC6H14HexaneC7H16HeptaneC8H18OctaneC9H20NonaneC10H22DecaneC11H24UndecaneC12H26DodecaneC13H28TridecaneC14H30TetradecaneC15H32PentadecaneC16H34Hexadecane,72,molecularNamemolecularnameformulaformulaC17H36HeptadecaneC18H38OctadecaneC19H40NonadecaneC20H42IcosaneC21H44HenicosaneC22H46DocosaneC23H48TricosaneC24H50TetracosaneC25H52PentacosaneC26H54HexacosaneC27H56HeptacosaneC28H58OctacosaneC29H60NonacosaneC30H62Triacontane,73,TableA2StructureNameCH3CH2CH2normal-orn-propyla(CH3)2CHisopropylCH3CH2CH2CH2n-butyla(CH3)2CHCH2isobutylCH3CH2CH(CH3)secondary-,orsec-butyl(CH3)3Ctertiary-,tert-,ort-butylbCH3CH2CH2CH2CH2n-pentyl(orn-amyl)a