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1、关于容量分析第1页，讲稿共37张，创作于星期日volumetric 体积的，容量的体积的，容量的unknown test sample未知试样未知试样coincide 符合，一致符合，一致stoichiometric 化学计量的化学计量的endpoint 终点终点titration 滴定滴定molarity 摩尔浓度摩尔浓度normality 当量浓度当量浓度equivalent 当量当量gram molecular weight 克分子量克分子量mole weight 分子量分子量curve 曲线曲线graph 曲线图曲线图representation 代表，象征代表，象征 marking
2、刻度，条纹，标志刻度，条纹，标志burette 滴定管滴定管tap water 自来水自来水rinse 冲洗冲洗drain 依次排出依次排出vinegar 醋醋methyl red 甲基红甲基红record 记录记录pH meter pH计计frost 霜，霜化霜，霜化render 致使，使成为致使，使成为simultaneously 同时地同时地in the case of 在在情况下，要是情况下，要是bring about 导致，引起导致，引起第2页，讲稿共37张，创作于星期日mol(e)-摩尔，分子 molarity n.摩尔浓度摩尔浓度moleculen.分子分子molecularad
3、j.分子的分子的nor-正，正常，降，去甲 normal adj.正常的，普通的正常的，普通的 normalize v.使正常化使正常化 normality n.当量浓度当量浓度 norbornene n.降冰片烯降冰片烯 noradrenaline n.去甲肾上腺素去甲肾上腺素前后缀前后缀第3页，讲稿共37张，创作于星期日坩埚坩埚crucible第4页，讲稿共37张，创作于星期日蒸发皿蒸发皿evaporationdish第5页，讲稿共37张，创作于星期日三脚架tripod第6页，讲稿共37张，创作于星期日泥三角Claytriangle第7页，讲稿共37张，创作于星期日beaker第8页，讲稿
4、共37张，创作于星期日烧瓶圆底烧瓶圆底烧瓶平底烧瓶平底烧瓶roundbottomflaskflatbottomflaskFlorenceflask第9页，讲稿共37张，创作于星期日烧瓶两口烧瓶两口烧瓶2-neck Boiling flask 第10页，讲稿共37张，创作于星期日集气瓶gas-jar第11页，讲稿共37张，创作于星期日Alcoholburnerwiregauzegas-jarroundbottomflaskStopper StopperRingstandwithring第12页，讲稿共37张，创作于星期日广口瓶Widemouthbottle第13页，讲稿共37张，创作于星期日滴瓶
5、Droppingbottle第14页，讲稿共37张，创作于星期日温度计100 mL10 mL量筒ThermometergraduatedcylinderMeasuringcylinder第15页，讲稿共37张，创作于星期日注意区别BuretteAcid buretteBase burette第16页，讲稿共37张，创作于星期日容量瓶容量瓶容量瓶volumetricflask第17页，讲稿共37张，创作于星期日BuretteclampBurettestandAcidburetteBaseburetteBurettestandwithdoubleclampsHoldingtwoburettevol
6、umetricflaskErlenmeyerflaskConicalflask第18页，讲稿共37张，创作于星期日分液漏斗separatingfunnel第19页，讲稿共37张，创作于星期日Buchnerfunnel第20页，讲稿共37张，创作于星期日AllihntypecondenserWesttypecondenserserpentinecondenser第21页，讲稿共37张，创作于星期日adapter第22页，讲稿共37张，创作于星期日Distillinghead第23页，讲稿共37张，创作于星期日TesttubeTesttuberackTesttubebrushtesttubecla
7、mp第24页，讲稿共37张，创作于星期日pipette pipettetriangularflask第25页，讲稿共37张，创作于星期日Plasticsqueezebottle第26页，讲稿共37张，创作于星期日Rubberpipettebulb第27页，讲稿共37张，创作于星期日Chemical analyses can be made by determining how much of a solution of known concentration is needed to react fully with an unknown test sample.The method is g
8、enerally referred to as volumetric analysis and consists of titrating the unknown solution with the one of known concentration(a standard solution).By titration,you can determine exactly how much of a reagent is required to bring about complete reaction of the test solution.F 化学分析的一般通过测定一已知浓度的溶液与未知试
9、样完全反应的关系来进行，化学分析的一般通过测定一已知浓度的溶液与未知试样完全反应的关系来进行，该方法一般也称为容量分析，方式是用已知浓度的标准溶液来滴定未知溶液。通过滴该方法一般也称为容量分析，方式是用已知浓度的标准溶液来滴定未知溶液。通过滴定分析，你可以测定与试样完全反应的标准溶液的消耗量。定分析，你可以测定与试样完全反应的标准溶液的消耗量。General principles 通用原理通用原理第28页，讲稿共37张，创作于星期日Usually,completion of the reaction is indicated by a sudden,visible change in the
10、reaction system that coincides with the stoichiometric relationship between moles or equivalents of-the reagent solution and the reactant in the test solution.A drop or two of an appropriate indicator solution produces a color change at the point where the reaction is complete-referred to as the end
11、point.F 一般来说，反应体系出现可见的突变表明反应已完全进行，此时滴定剂与被滴定物质的摩尔一般来说，反应体系出现可见的突变表明反应已完全进行，此时滴定剂与被滴定物质的摩尔数或当量满足一定的化学计量关系。数或当量满足一定的化学计量关系。12滴合适的指示剂可在某个时刻产生颜色突变，此滴合适的指示剂可在某个时刻产生颜色突变，此时滴定反应完全进行，称为滴定终点。时滴定反应完全进行，称为滴定终点。Molarity is the number of moles(gram-molecular weights)of substance per liter of solution.The mole wei
12、ght of sulfuric acid is 98.08 g,and therefore,1 mole of H2SO4 contains 98.08 g.If 49.04 g are diluted to 1 liter then the concentration is 0.49 or 0.5M.In the case of hydrochloric acid,HCl,a 1 M solution is prepared by taking 36.465 g of HC1 and diluting to 1 liter.The procedure is the same for base
13、s.F 摩尔浓度是每升溶液中含有某物质的摩尔数（或克分子量）。硫酸的克分子量为摩尔浓度是每升溶液中含有某物质的摩尔数（或克分子量）。硫酸的克分子量为98.08 g，因，因此此1 M的硫酸溶液含有的硫酸溶液含有98.08 g的硫酸；如果的硫酸；如果49.04 g的硫酸稀释到的硫酸稀释到1 L溶液，那硫酸的浓溶液，那硫酸的浓度为度为0.49 或或0.5 M。以盐酸为例，。以盐酸为例，1 M盐酸由盐酸由1 M HCl溶于溶于1 L水制得，碱的情况亦是如此。水制得，碱的情况亦是如此。第29页，讲稿共37张，创作于星期日Normality is the number of equivalent weig
14、hts of substance per liter of solution.The equivalent weight of an acid is the weight of that acid capable of furnishing 1 mole of protons(H+),and the equivalent weight of a base is the weight of base capable of receiving 1 mole of protons.The equivalent weight of H2SO4 is 98.08g/2 or 49.04 g.Theref
15、ore,a normal solution(N)of H2SO4 contains 49.04g per liter.F 当量浓度是一升溶液中某物质的当量数，酸的当量指能提供当量浓度是一升溶液中某物质的当量数，酸的当量指能提供1 摩尔氢离子的酸的质量，摩尔氢离子的酸的质量，碱的当量是接受碱的当量是接受1摩尔氢离子的碱的质量。硫酸的当量为摩尔氢离子的碱的质量。硫酸的当量为98.08 g除以除以2或或49.04 g，因此一当量的硫酸溶液每升含有因此一当量的硫酸溶液每升含有49.04 g硫酸。硫酸。The normality of an acid or base of unknown concent
16、ration may be determined by titration.The advantage of using normality rather than molarity is that equal volumes of solutions of equal normalities have identical capacities for neutralization,because they contain the same number of equivalent weights.F 未知浓度的酸未知浓度的酸/碱的当量浓度可用滴定分析测定，当量浓度优于摩尔浓度在于相同体积碱的
17、当量浓度可用滴定分析测定，当量浓度优于摩尔浓度在于相同体积的等当量溶液具有相同的中和能力，因为两者具有相同的当量数。的等当量溶液具有相同的中和能力，因为两者具有相同的当量数。第30页，讲稿共37张，创作于星期日In a titration,we compare equivalent weights of acid and base.The number of equivalents of acid is equal to the product of the volume of the acid solution and its normality.The number of equivale
18、nts of base is the product of the volume of the base solution and its normality.Neutralization has taken place when the number of equivalents of acid is equal to the number of equivalents of base.F 滴定时我们会比较酸与碱的当量。酸的当量数等于酸的体积乘以它的当量浓度，滴定时我们会比较酸与碱的当量。酸的当量数等于酸的体积乘以它的当量浓度，碱的当量数等于碱的体积乘以当量浓度。当酸与碱的当量数相等时，中和
19、反应发生。碱的当量数等于碱的体积乘以当量浓度。当酸与碱的当量数相等时，中和反应发生。第31页，讲稿共37张，创作于星期日Care must be exercised throughout the titration procedure.The burette should be thoroughly cleaned with soap and water,rinsed with tap water,and finally,rinsed with distilled water.Just before use,the burette should be rinsed with two 5-ml
20、portions of the solution to be used in the burette.This is done by holding the burette in a semi-horizontal position and rolling the solution around the entire inner surface.Allow the final rinsing to drain through the tip.F 滴定过程要十分小心，滴定管必须用肥皂和水完全洗净，再依次用自来水和蒸馏滴定过程要十分小心，滴定管必须用肥皂和水完全洗净，再依次用自来水和蒸馏水冲洗。使
21、用前滴定管还要用水冲洗。使用前滴定管还要用5-mL的使用溶液清洗两遍，其过程为：将滴定管半的使用溶液清洗两遍，其过程为：将滴定管半平放，转动滴定管使管内溶液与内表面充分浸润，然后从滴定管尖嘴放掉润洗溶平放，转动滴定管使管内溶液与内表面充分浸润，然后从滴定管尖嘴放掉润洗溶液。液。Procedure 步骤步骤Fill the burette to a point above the top marking and allow the solution to run out until the bottom of the meniscus is just at the top marking of
22、the burette.The burette tip must be completely filled to deliver the volume measured.F 在滴定管内引入溶液到高于顶端刻度线以上，然后从尖嘴处放出溶液直至凹液面与顶端刻线在滴定管内引入溶液到高于顶端刻度线以上，然后从尖嘴处放出溶液直至凹液面与顶端刻线齐平，滴定管尖嘴要完全充满溶液以放出准确的体积。齐平，滴定管尖嘴要完全充满溶液以放出准确的体积。第32页，讲稿共37张，创作于星期日In addition,the burette must be cleaned thoroughly after use becaus
23、e sodium hydroxide and other types of solutions will eventually frost the glass and render an expensive piece of equipment useless.F 此外滴定管在使用后也要完全洗净，因为氢氧化钠和其它类型的试剂会腐蚀玻璃，导致滴定此外滴定管在使用后也要完全洗净，因为氢氧化钠和其它类型的试剂会腐蚀玻璃，导致滴定管的某个昂贵组件无法使用。管的某个昂贵组件无法使用。1.Titration of Vinegar Measure 50 ml of vinegar with a pipett
24、e and pour into a 250-ml beaker.Add 2 drops of phenolphthalein indicator.Fill a burette with a 1 N solution of sodium hydroxide(NaOH)and draw out the excess as described above.From the burette add NaOH to the beaker of vinegar until 1 drop of NaOH produces a pale pink color in the solution.Maintain
25、constant stirring.The appearance of pink tells you that the acid has been neutralized by the base and there is now 1 drop of excess base which has turned the indicator.Read the burette and record this reading as the volume of base used to neutralize the acid.F 1.食醋的滴定：用吸液管量取食醋的滴定：用吸液管量取50mL的食醋到的食醋到2
26、50 mL烧杯，加入两滴酚酞指示剂，将烧杯，加入两滴酚酞指示剂，将1当量的当量的氢氧化钠浓度装入碱式滴定管，并按上述操作放出多余的溶液。从滴定管将氢氧化钠加入到烧杯与氢氧化钠浓度装入碱式滴定管，并按上述操作放出多余的溶液。从滴定管将氢氧化钠加入到烧杯与食醋反应，直至过量的一滴氢氧化钠使酚酞产生浅粉色，滴定过程中要一直振荡溶液。粉色的出现食醋反应，直至过量的一滴氢氧化钠使酚酞产生浅粉色，滴定过程中要一直振荡溶液。粉色的出现表明酸已完全被碱中和，过量的一滴氢氧化钠与指示剂反应使其变色。读出滴定管的刻度，记下中表明酸已完全被碱中和，过量的一滴氢氧化钠与指示剂反应使其变色。读出滴定管的刻度，记下中和食
27、醋的氢氧化钠的体积。和食醋的氢氧化钠的体积。第33页，讲稿共37张，创作于星期日According to the equation：NaOH+CH3COOH Na+CH3COO-+H2OOne molecule of NaOH neutralizes one molecule of acetic acid,or one gram-molecular weight of NaOH neutralizes one gram-molecular weight of acetic acid.Calculate the amount of acetic acid present in the vineg
28、ar.Report this amount as the percentage of acetic acid.F 根据反应式根据反应式NaOH+CH3COOH Na+CH3COO-+H2O，一分子氢氧化钠中和一分子的乙，一分子氢氧化钠中和一分子的乙酸，或一克分子量的氢氧化钠中和一克分子量的乙酸酸，或一克分子量的氢氧化钠中和一克分子量的乙酸。然后计算出醋中乙酸的含量，用乙酸的百分。然后计算出醋中乙酸的含量，用乙酸的百分比来表示。比来表示。2.Standard Titration Curve If a pH meter is available,repeat the above process u
29、sing a pH meter for constantly determining the pH.When the endpoint is reached,continue adding the base to expand the curve further.Make a graph for this titration.F 2.标准滴定曲线：如果有一个标准滴定曲线：如果有一个pH计，重复上述滴定过程，同时用计，重复上述滴定过程，同时用pH计测定体系的计测定体系的pH值，到值，到达滴定终点后，继续滴加氢氧化钠并记录达滴定终点后，继续滴加氢氧化钠并记录pH值，作一张（滴定剂消耗量值，作一张（
30、滴定剂消耗量vs pH值的）滴定值的）滴定曲线图。曲线图。第34页，讲稿共37张，创作于星期日3.Equivalents of Acid Using the 1 N solution of NaOH,determine the number of equivalents in two samples of benzoic acid.Carry out the procedure for the two determinations simultaneously.From this value calculate the equivalent weight of the acid.The sol
31、id should be weighed in a beaker and should be dissolved in about 25 ml of ethyl alcohol before titration with the base.Between 2.0 and 2.2 g of the solid provide the best results.Record all data and make all calculations necessary to determine the equivalent weight of the solid acid.Compare your ex
32、perimental value with the equivalent weight of benzoic acid(calculated from the formula)and determine the percentage of error of your work.F 3.酸的当量：用一当量浓度的氢氧化钠，测定两个苯甲酸样品的当量数，两个测定同时进行，通酸的当量：用一当量浓度的氢氧化钠，测定两个苯甲酸样品的当量数，两个测定同时进行，通过滴定体积计算出酸的当量。先将固体酸称到烧杯中，加入过滴定体积计算出酸的当量。先将固体酸称到烧杯中，加入25 mL乙醇溶解再用碱滴定，乙醇溶解再用碱滴
33、定，2.02.2 g样品可获得最佳的结果。记录所有数据，完成必要的计算过程得到固体酸的当量。将你实验样品可获得最佳的结果。记录所有数据，完成必要的计算过程得到固体酸的当量。将你实验的测定值与苯甲酸的当量（由分子式算得）比较，计算你的测定结果的误差。的测定值与苯甲酸的当量（由分子式算得）比较，计算你的测定结果的误差。第35页，讲稿共37张，创作于星期日Questions to Consider(l)Calculate the percentage of acetic acid in vinegar.(2)What is the pH range for phenolphthalein?(3)Wh
34、y should the solution in the flask constantly be stirred?(4)What determines the pH of a solution at the end of a titration of an acid with a base?(5)Consider a hypothetical experiment in which you weighed out 2.0 g of oxalic acid and titrated it with 43 ml of 1.5N NaOH.What is the equivalent weight
35、of oxalic acid?(6)When all of the acetic acid was neutralized by the sodium hydroxide,was the pH=7?Explain.F 思考题：思考题：(1)计算醋中乙酸的百分含量；计算醋中乙酸的百分含量；(2)酚酞的适用酚酞的适用pH范围是多少？范围是多少？(3)为什么锥形瓶为什么锥形瓶中的溶液要一直振荡？；中的溶液要一直振荡？；(4)碱滴定酸到达终点时体系的碱滴定酸到达终点时体系的pH取决于什么物质？取决于什么物质？(5)假设有一个滴假设有一个滴定实验称取了定实验称取了2.0 g的乙二酸，用的乙二酸，用1.5当量浓度的氢氧化钠滴定所消耗的体积为当量浓度的氢氧化钠滴定所消耗的体积为43 mL，那么乙，那么乙二酸的当量是多少？二酸的当量是多少？(6)当氢氧化钠中和完所有乙酸时，此时溶液的当氢氧化钠中和完所有乙酸时，此时溶液的pH是否为是否为7，为什么？，为什么？第36页，讲稿共37张，创作于星期日感谢大家观看第37页，讲稿共37张，创作于星期日