項(xiàng)目八：常規(guī)物理常數(shù)與性能分析任務(wù)三：沸點(diǎn)和沸程的測(cè)定

沸點(diǎn)和沸程概念及測(cè)定方法課程：工業(yè)分析中文Scenario8:PhysicalconstantsandperformancetestingTask3：DeterminationofboilingpointandboilingrangeTheconceptsandmeasurementmethodsofboilingpointandboilingrangeCourse:IndustrialAnalysisEglish

沸騰：當(dāng)液體受熱后溫度升高，它的蒸氣壓也隨之上升，當(dāng)液體的蒸氣壓與大氣壓相等時(shí)，稱為沸騰。沸點(diǎn)：在標(biāo)準(zhǔn)狀態(tài)下，液體沸騰時(shí)的溫度。標(biāo)示為Tbp。沸程：揮發(fā)性有機(jī)液體樣品，在標(biāo)準(zhǔn)規(guī)定下蒸餾，第一滴餾出物從冷凝管末端落下的瞬間溫度（初餾點(diǎn)）至蒸餾瓶底最后一滴液體蒸發(fā)的瞬間溫度（終餾點(diǎn)）之間的溫度間隔。一、基本概念中文

Boiling:Whenaliquidisheatedanditstemperaturerises,itsvaporpressurealsoincreases.Whenthevaporpressureoftheliquidisequaltoatmosphericpressure,itiscalledboiling.Boilingpoint:Thetemperatureatwhichaliquidboilsunderstandardconditions.MarkedasTbp.Boilingrange:Thetemperatureintervalbetweentheinstanttemperature(initialboilingpoint)atwhichthefirstdropofdistillatefallsfromtheendofthecondensertubeandtheinstanttemperature(finalboilingpoint)atwhichthelastdropofliquidevaporatesatthebottomofthedistillationflask,whenavolatileorganicliquidsampleisdistilledunderstandardspecifications.一、BasicconceptsEglish

初餾點(diǎn)：是指油品在規(guī)定的條件下進(jìn)行餾程的測(cè)定中，當(dāng)冷凝管中流出第一滴冷凝液時(shí)的氣相溫度，以℃表示。

終餾點(diǎn)：是指油品在規(guī)定的條件下進(jìn)行餾程的測(cè)定，蒸餾過(guò)程中的最高氣相溫度，以℃表示。

餾分：是指在某一溫度范圍蒸出的餾出物。如汽油餾分、煤油餾分、柴油餾分及潤(rùn)滑油餾分等。溫度范圍窄的稱為窄餾分，溫度范圍寬的稱為寬餾分。

干點(diǎn)：蒸餾燒瓶底部最后一滴液體汽化的瞬間所測(cè)得的氣相溫度，以℃表示。中文Initialboilingpoint:referstothegasphasetemperatureofanoilproductwhenthefirstdropofcondensateflowsoutofthecondensertubeduringdistillationunderspecifiedconditions,expressedin℃.Finalboilingpoint:referstothehighestgasphasetemperatureduringthedistillationprocessofanoilproductunderspecifiedconditions,expressedin℃.Distillate:referstothedistillatedistilledwithinacertaintemperaturerange.Suchasgasolinefraction,kerosenefraction,dieselfraction,andlubricatingoilfraction.Anarrowtemperaturerangeiscalledanarrowfraction,whileawidetemperaturerangeiscalledawidefraction.Drypoint:Thegasphasetemperaturemeasuredatthemomentwhenthelastdropofliquidatthebottomofthedistillationflaskvaporizes,expressedin℃.Eglish

餾出溫度：油品在規(guī)定的條件下進(jìn)行餾程的測(cè)定中，量筒內(nèi)回收的冷凝液達(dá)到某一規(guī)定體積（mL）時(shí)所同時(shí)觀察的溫度，以℃表示。50%餾出溫度：是指油品在規(guī)定的條件下進(jìn)行餾程的測(cè)定中，當(dāng)餾出物體積為裝入試樣的50%時(shí)，蒸餾瓶?jī)?nèi)的氣相溫度，以℃表示。中文Distillationtemperature:Thetemperatureobservedwhentherecoveredcondensateinthegraduatedcylinderreachesaspecifiedvolume(mL)duringdistillationofanoilproductunderspecifiedconditions,expressedin℃.50%DistillationTemperature:referstothegasphasetemperatureinsidethedistillationbottlewhenthevolumeofthedistillateis50%ofthesamplewhentheoilisdistilledunderspecifiedconditions,expressedin℃.Eglish

回收百分?jǐn)?shù)：是指油品在規(guī)定的條件下進(jìn)行餾程的測(cè)定中，觀察到的最大回收體積所占加入試樣的百分?jǐn)?shù)。

殘留物百分?jǐn)?shù)：是指油品在規(guī)定的條件下進(jìn)行餾程的測(cè)定中，用總回收百分?jǐn)?shù)減回收百分?jǐn)?shù)之差，或者直接測(cè)定殘留物體積（mL）所占加入試樣的百分?jǐn)?shù)。

總回收百分?jǐn)?shù)：指油品在規(guī)定的條件下進(jìn)行餾程的測(cè)定中，所得燒瓶里殘留物百分?jǐn)?shù)和回收百分?jǐn)?shù)之和。損失百分?jǐn)?shù)：指油品在規(guī)定條件下進(jìn)行餾程的測(cè)定中，用100減總回收百分?jǐn)?shù)之差。中文

Recoverypercentage:Thepercentageofthemaximumrecoveryvolumeobservedwhentheoilisdistilledunderspecifiedconditionstothevolumeoftheaddedsample.Residuepercentage:Thepercentageofresidualvolume(mL)intheflasktothevolumeofthesampleaddedwhentheoilisdistilledunderspecifiedconditions.Totalrecoverypercentage:Thesumofthepercentageofresidueintheflaskandtherecoverypercentagewhentheoilisdistilledunderspecifiedconditions.Losspercentage:Whentheoilisdistilledunderspecifiedconditions,thedifferencebetween100andthetotalrecoverypercentageisthelosspercentage.Eglish在脂肪族化合物的異構(gòu)體中，直鏈異構(gòu)體比有側(cè)鏈的異構(gòu)體的沸點(diǎn)高。側(cè)鏈越多，沸點(diǎn)越低。在醇、鹵代物、硝基化合物的異構(gòu)體中，伯異構(gòu)體沸點(diǎn)最高，仲異構(gòu)體次之，叔異構(gòu)體最低。

在順?lè)串悩?gòu)體中，順式異構(gòu)體沸點(diǎn)比反式高。

在多雙鍵的化合物中，有共軛雙鍵的化合物有較高的沸點(diǎn)。

鹵代烴、醇、醛、酮、酸的沸點(diǎn)比相應(yīng)的烴高。

在同系列中，相對(duì)分子量增大，沸點(diǎn)增高，但遞增值逐漸減小。二、沸點(diǎn)（或沸程）與分子結(jié)構(gòu)的關(guān)系中文Intheisomersofaliphaticcompounds,straightchainisomershaveahigherboilingpointthanthosewithsidechains.Themoresidechainsthereare,thelowertheboilingpoint.Amongtheisomersofalcohols,halogenatedcompounds,andnitrocompounds,theprimaryisomerhasthehighestboilingpoint,followedbythesecondaryisomer,andthetertiaryisomerhasthelowestboilingpoint.Incistransisomers,theboilingpointofcisisomersishigherthanthatoftransisomers.Incompoundswithmultipledoublebonds,compoundswithconjugateddoublebondshavehigherboilingpoints.Halogenatedhydrocarbons,alcohols,aldehydes,ketones,andacidshavehigherboilingpointsthantheircorrespondinghydrocarbons.Inthesameseries,therelativemolecularweightincreases,theboilingpointincreases,buttheincrementgraduallydecreases.二、Therelationshipbetweenboilingpoint(orboilingrange)andmolecularstructureEglish1、沸點(diǎn)測(cè)定方法三、沸點(diǎn)和沸程測(cè)定方法標(biāo)準(zhǔn)方法毛細(xì)管法中文1、Methodfordeterminingboilingpoint三、MethodfordeterminingboilingpointandboilingrangestandardmethodcapillarymethodEglish（1）標(biāo)準(zhǔn)方法

在標(biāo)準(zhǔn)狀況下，液體的沸騰溫度即為該液體的沸點(diǎn)。當(dāng)液體溫度升高時(shí)，其蒸氣壓上升，當(dāng)蒸氣壓與大氣壓力相等時(shí)，開始沸騰，溫度不再上升，此時(shí)溫度即為沸點(diǎn)標(biāo)準(zhǔn)方法測(cè)定裝置1-燒瓶，2-試管，3、4膠塞，5-主溫度計(jì)，6-輔助溫度計(jì)，7-側(cè)孔，8-溫度計(jì)中文（1）Standardmethod

Understandardconditions,theboilingtemperatureofaliquidisitsboilingpoint.

Whenthetemperatureofaliquidrises,itsvaporpressurerises.Whenthevaporpressureisequaltotheatmosphericpressure,boilingbeginsandthetemperaturenolongerrises.Atthispoint,thetemperatureistheboilingpointDevicediagramformeasuringboilingpointusingstandardmethods1-flask;2-testtube;3,4-rubberplugs;5-mainthermometer;6-auxiliarythermometer;7-sidehole;8-ThermometerEglish（2）毛細(xì)管法樣品量很少或樣品珍貴時(shí)用該法。測(cè)定時(shí)將少量樣品裝入沸點(diǎn)管，內(nèi)插一支上端封口的毛細(xì)管作內(nèi)管。加熱至有連續(xù)氣泡從內(nèi)管逸出，停止加熱，當(dāng)氣泡停止逸出而液體剛要進(jìn)入內(nèi)管時(shí)的溫度為沸點(diǎn)。中文（2）CapillarymethodThismethodisusedwhenthesamplesizeissmallorthesampleisprecious.Duringthemeasurement,asmallamountofsampleisloadedintoaboilingpointtube,andacapillarytubewithanupperendsealedisinsertedastheinnertube.Heatuntilcontinuousbubblesescapefromtheinnertube,stopheating,andthetemperatureatwhichthebubblesstopescapingandtheliquidisabouttoentertheinnertubeistheboilingpoint.boilingpointtubeinn