PREFACE TO
FIFTEENTH EDITION
This new edition,the?fth under the aegis of the present editor,remains the one-volume source of factual information for chemists,both professionals and students—the?rst place in which to“look it up”on the spot.The aim is to provide suf?cient data to satisfy all one’s general needs without recourse to other reference sources.A user will?nd this volume of value as a time-saverbecause of the many tables of numer ical data which have been especially compiled.
Descriptive properties for a basic group of approximately4300organic compounds are compiled in Section1,an increase of300entries.All entries are listed alphabetically according to the senior pre?x of the name.The data for each organic compound include (where available)name,structural formula,formula weight,Beilstein reference(or if un-available,the entry to the Merck Index,12th ed.),density,refractive index,melting point, boiling point,?ash point,and solubility(citing numerical values if known)in water and
various common organic solvents.Structural formulas either too complex or too ambig-uous to be rendered as line formulas are grouped at the bottom of each facing double page on which the entries appear.Alternative names,as well as trivial names of long-standing usage,are listed in their respective alphabetical order at the bottom of each double page in the regular alphabetical sequence.Another feature that assists the user in locating a desired entry is the empirical formula index.
Section2on General Information,Conversion Tables,and Mathematics has had the table on general conversion factors thoroughly reworked.Similarly the material on Statis-tics in Chemical Analysis has had its contents more than doubled.
Descriptive properties for a basic group of inorganic compounds are compiled in Section 3,which has undergone a small increase in the number of entries.Many entries under the column“Solubility”supply the reader with precise quantities dissolved in a stated solvent and at a given temperature.
Several portions of Section4,Properties of Atoms,Radicals,and Bonds,have been signi?cantly enlarged.For example,the entries under“Ionization Energy of Molecular and Radical Species”now number740and have an additional column with the enthalpy of formation of the ions.Likewise,the table on“Electron Af?nities of the Elements, Molecules,and Radicals”now contains about225entries.The Table of Nuclides has material on additional radionuclides,their radiations,and the neutron capture cross sec-tions.
Revised material for Section5includes the material on surface tension,viscosity,di-electric constant,and dipole moment for organic compounds.In order to include more data at several temperatures,the material has been divided into two separate tables.Ma-terial on surface tension and viscosity constitute the?rst table with715entries;included is the temperature range of the liquid phase.Material on dielectric constant and dipole
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moment constitute another table of1220entries.The additional data at two or more tem-peratures permit interpolation for intermediate temperatures and also permit limited ex-trapolation of the data.The Properties of Combustible Mixtures in Air has been revised and expanded to include over450compounds.Flash points ar e to be found in Section1. Completely revised are the tables on Thermal Conductivity for gases,liquids,and solids. Van derWaals’constants forgases has been br ought up to date and expanded to over500 substances.
Section6,which includes Enthalpies and Gibbs Energies of Formation,Entropies,and Heat Capacities of Organic and Inorganic Compounds,and Heats of Melting,Vaporization, and Sublimation and Speci?c Heat at Various Temperatures for organic and inorganic compounds,has expanded by11pages,but the majoradditions have involved data in columns where it previously was absent.More material has also been included for critical temperature,critical pressure,and critical volume.
The section on Spectroscopy has been retained but with some revisions and expansion. The section includes ultraviolet-visible spectroscopy,?uorescence,infrared and Raman spectroscopy,and X-ray spectrometry.Detection limits are listed for the elements when using?ame emission,?ame atomic absorption,electrothermal atomic absorption,argon induction coupled plasma,and?ame atomic?uorescence.Nuclear magnetic resonance embraces tables for the nuclear properties of the elements,proton chemical shifts and coupling constants,and similar material for carbon-13,boron-11,nitrogen-15,?uorine-19,silicon-19,and phosphorus-31.
In Section8,the material on solubility constants has been doubled to550entries. Sections on proton transfer reactions,including some at various temperatures,formation constants of metal complexes with organic and inorganic ligands,buffer solutions of all types,reference electrodes,indicators,and electrode potentials are retained with some revisions.The material on conductances has been revised and expanded,particularly in the table on limiting equivalent ionic conductances.
Everything in Sections9and10on physiochemical relationships,and on polymers, rubbers,fats,oils,and waxes,respectively,has been retained.
Section11,Practical Laboratory Information,has undergone signi?cant changes and expansion.Entries in the table on“Molecular Elevation of the Boiling Point”have been increased.McReynolds’constants for stationary phases in gas chromatography have been reorganized and expanded.The guide to ion-exchange resins and discussion is new and embraces all types of column packings and membrane materials.Gravimetric factors have been altered to re?ect the changes in atomic weights for several elements.Newly added are tables listing elements precipitated by general analytical reagents,and giving equations for the redox determination of the elements with their equivalent weights.Discussion on the topics of precipitation and complexometric titrations include primary standards and indicators for each analytical technique.A new topic of masking and demasking agents includes discussion and tables of masking agents forvar ious elements,foranions and neutral molecules,and common demasking agents.A table has been added listing the common amino acids with theirpI and p K
values and their3-letterand1-letterabbr evi-
a
https://www.doczj.com/doc/0412677971.html,stly a9-page table lists the threshold limit value(TLV)for gases and vapors.
As stated in earlier prefaces,every effort has been made to select the most useful and reliable information and to record it with accuracy.However,the editor’s50years of
PREFACE TO FIFTEENTH EDITION ix involvement with textbooks and handbooks bring a realization of the opportunities for gremlins to exert their inevitable mischief.It is hoped that users of this handbook will continue to offer suggestions of material that might be included in,or even excluded from, future editions and call attention to errors.These communications should be directed to the editor.The street address will change early in1999,as will the telephone number. However,the e-mail address should remain as“pd105@https://www.doczj.com/doc/0412677971.html,.”
Knoxville,TN John A.Dean
PREFACE TO
FOURTEENTH EDITION
Perhaps it would be simplest to begin by stating the ways in which this new edition,the fourth under the aegis of the present editor,has not been changed.It remains the one-volume source of factual information for chemists,both professionals and students—the?rst place in which to“look it up”on the spot.The aim is to provide suf?cient data to satisfy all one’s general needs without recourse to other reference sources.Even the worker with the facilities of a comprehensive library will?nd this volume of value as a time-saverbecause of the many tables of numer ical data which have been especially compiled.
The changes,however,are both numerous and signi?cant.First of all,there is a change in the organization of the subject matter.For example,material formerly contained in the section entitled Analytical Chemistry is now grouped by operational categories:spectroscopy;electrolytes,electro-motive force,and chemical equilibrium;and practical laboratory information.Polymers,rubbers, fats,oils,and waxes constitute a large independent section.
Descriptive properties for a basic group of approximately4000organic compounds are compiled
in Section1.These follow a concise introduction to organic nomenclature,including the topic of stereochemistry.Nomenclature is consistent with the1979rules of the Commission on Nomencla-ture,International Union of Pure and Applied Chemistry(IUPAC).All entries are listed alphabeti-cally according to the senior pre?x of the name.The data for each organic compound include(where available)name,structural formula,formula weight,Beilstein reference,density,refractive index, melting point,boiling point,?ash point,and solubility(citing numerical values if known)in water and various common organic solvents.Structural formulas either too complex or too ambiguous to be rendered as line formulas are grouped at the bottom of the page on which the entries appear. Alternative names,as well as trivial names of long-standing usage,are listed in their respective alphabetical order at the bottom of each page in the regular alphabetical sequence.Another feature that assists the user in locating a desired entry is the empirical formula index.
Section2combines the former separate section on Mathematics with the material involving General Information and Conversion Tables.The fundamental physical constants re?ect values rec-ommended in1986.Physical and chemical symbols and de?nitions have undergone extensive re-vision and expansion.Presented in14categories,the entries follow recommendations published in 1988by the IUPAC.The table of abbreviations and standard letter symbols provides,in a sense,an alphabetical index to the foregoing tables.The table of conversion factors has been modi?ed in view of recent data and inclusion of SI units;cross-entries for“archaic”or unusual entries have been curtailed.
Descriptive properties for a basic group of approximately1400inorganic compounds are com-piled in Section3.These follow a concise,revised introduction to inorganic nomenclature that follows the recommendations of the IUPAC published in1990.In this section are given the exact atomic(or formula)weight of the elements accompanied,when available,by the uncertainty in the ?nal?gure given in parentheses.
In Section4the data on bond lengths and strengths have been vastly increased so as to include not only the atomic and effective ionic radii of elements and the covalent radii for atoms,but also the bond lengths between carbon and other elements and between elements other than carbon.All
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lengths are given in picometers(SI unit).Effective ionic radii are tabulated as a function of ion charge and coordination number.Bond dissociation energies are given in kilojoules per mole with the uncertainty of the?nal?gure(s)given in parentheses when known.New tables include bond dipole moments,group dipole moments,work functions of the elements,and relative abundances of the naturally occurring elements.The table of nuclides has been shortened and includes only the more commonly encountered nuclides;tabulations list half-life,natural abundance,cross-section to thermal neutrons,and radiation emitted upon disintegration.Entries have been updated.
Revised material in Section5includes an extensive tabulation of binary and ternary azeotropes comprising approximately850entries.Over975compounds have values listed for viscosity,di-electric constant,dipole moment,and surface tension.Whenever possible,data for viscosity and dielectric constant are provided at two temperatures to permit interpolation for intermediate tem-peratures and also to permit limited extrapolation of the data.The dipole moments are often listed for different physical states.Values for surface tension can be calculated over a range of temperatures from two constants that can be?tted into a linear equation.Also extensively revised and expanded are the properties of combustible mixtures in air.A table of triple points has been added.
The tables in Section6contain values of the enthalpy and Gibbs energy of formation,entropy, and heat capacity at?ve temperatures for approximately2000organic compounds and1500inor-ganic compounds,many in more than one physical state.Separate tabulations have enthalpies of melting,vaporization,transition,and sublimation for organic and inorganic compounds.All values are given in SI units(joule)and have been extracted from the latest sources such as JANAF Ther-mochemical Tables,3d ed.(1986);Thermochemical Data of Organic Compounds,2d ed.(1986); and Enthalpies of Vaporization of Organic Compounds,published underthe auspices of the IUPAC (1985).Also updated is the material on critical properties of elements and compounds.
The section on Spectroscopy has been expanded to include ultraviolet-visible spectroscopy,?uorescence,Raman spectroscopy,and mass spectroscopy.Retained sections have been thoroughly revised:in particular,the tables on electronic emission and atomic absorption spectroscopy,nuclear magnetic resonance,and infrared spectroscopy.Detection limits are listed for the elements when using?ame emission,?ame atomic absorption,electrothermal atomic absorption,argon ICP,and ?ame atomic?uorescence.Nuclear magnetic resonance embraces tables for the nuclear properties of the elements,proton chemical shifts and coupling constants,and similar material for carbon-13, boron-11,nitrogen-15,?uorine-19,silicon-29,and phosphorus-31.
Section8now combines all the material on electrolytes,electromotive force,and chemical equi-librium,some of which had formerly been included in the old“Analytical Chemistry”section of earlier editions.Material on the half-wave potentials of inorganic and organic materials has been thoroughly revised.The tabulation of the potentials of the elements and their compounds re?ects recent IUPAC(1985)recommendations.
An extensive new Section10is devoted to polymers,rubbers,fats,oils,and waxes.A discussion of polymers and rubbers is followed by the formulas and key properties of plastic materials.For each member and type of the plastic families there is a tabulation of their physical,electrical, mechanical,and thermal properties and characteristics.A similar treatment is accorded the various types of rubber materials.Chemical resistance and gas permeability constants are also given for rubbers and plastics.The section concludes with various constants of fats,oils,and waxes.
The practical laboratory information contained in Section11has been gathered from many of the previous sections of earlier editions.This material has been supplemented with new material under separation methods,gravimetric and volumetric analysis,and laboratory solutions.Signi?cant new tables under separation methods include:properties of solvents for chromatography,solvents having the same refractive index and the same density,McReynolds’constants for stationary phases in gas chromatography,characteristics of selected supercritical?uids,and typical performances in HPLC for various operating conditions.Under gravimetric and volumetric analysis,gravimetric factors,equations and equivalents for volumetric analysis,and titrimetric factors have been retained
PREFACE TO FOURTEENTH EDITION xiii along with the formation constants of EDTA metal complexes.In this age of awareness of chemical dangers,tables have been added for some common reactive and incompatible chemicals,chemicals recommended for refrigerated storage,and chemicals which polymerize or decompose on extended storage at low temperature.Updated is the information about the U.S.Standard Sieve Series.Ther-mometry data have been revised to bring them into agreement with the new International Temper-ature Scale–1990,and data for type N thermocouples are included.
Every effort has been made to select the most useful and most reliable information and to record it with accuracy.However,the editor’s many years of involvement with handbooks bring a realiza-tion of the opportunities for gremlins to exert their inevitable mischief.It is hoped that users of this handbook will offer suggestions of material that might be included in,or even excluded from,future editions and call attention to errors.These communications should be directed to the editor at his home address(or by telephone).
John A.Dean
PREFACE TO
FIRST EDITION
This book is the result of a number of years’experience in the compiling and editing of data useful to chemists.In it an effort has been made to select material to meet the needs of chemists who cannot command the unlimited time available to the research specialist,or who lack the facilities of a large technical library which so often is not conveniently located at many manufacturing centers. If the information contained herein serves this purpose,the compiler will feel that he has accom-plished a worthy task.Even the worker with the facilities of a comprehensive library may?nd this volume of value as a time-saverbecause of the many tables of numer ical data which have been especially computed forthis pur pose.
Every effort has been made to select the most reliable information and to record it with accuracy. Many years of occupation with this type of work bring a realization of the opportunities for the occurrence of errors,and while every endeavor has been made to prevent them,yet it would be remarkable if the attempts towards this end had always been successful.In this connection it is desired to express appreciation to those who in the past have called attention to errors,and it will be appreciated if this be done again with the present compilation for the publishers have given
their assurance that no expense will be spared in making the necessary changes in subsequent printings.
It has been aimed to produce a compilation complete within the limits set by the economy of available space.One dif?culty always at hand to the compilerof such a book is that he must decide what data are to be excluded in order to keep the volume from becoming unwieldy because of its size.He can hardly be expected to have an expert’s knowledge of all branches of the science nor the intuition necessary to decide in all cases which particular value to record,especially when many differing values are given in the literature for the same constant.If the expert in a particular?eld will judge the usefulness of this book by the data which it supplies to him from?elds other than his specialty and not by the lack of highly specialized information in which only he and his co-workers are interested(and with which he is familiar and for which he would never have occasion to consult this compilation),then an estimate of its value to him will be apparent.However,if such specialists will call attention to missing data with which they are familiar and which they believe others less specialized will also need,then works of this type can be improved in succeeding editions.
Many of the gaps in this volume are caused by the lack of such information in the literature.It is hoped that to one of the most important classes of workers in chemistry,namely the teachers,the book will be of value not only as an aid in answering the most varied questions with which they are confronted by interested students,but also as an inspiration through what it suggests by the gaps and inconsistencies,challenging as they do the incentive to engage in the creative and experimental work necessary to supply the missing information.
While the principal value of the book is for the professional chemist or student of chemistry,it should also be of value to many people not especially educated as chemists.Workers in the natural sciences—physicists,mineralogists,biologists,pharmacists,engineers,patent attorneys,and librar-ians—are often called upon to solve problems dealing with the properties of chemical products or materials of construction.For such needs this compilation supplies helpful information and will serve not only as an economical substitute for the costly accumulation of a large library of mono-graphs on specialized subjects,but also as a means of conserving the time required to search for
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information so widely scattered throughout the literature.For this reason especial care has been taken in compiling a comprehensive index and in furnishing cross references with many of the tables.
It is hoped that this book will be of the same usefulness to the worker in science as is the dictionary to the worker in literature,and that its resting place will be on the desk rather than on the bookshelf. Cleveland,Ohio https://www.doczj.com/doc/0412677971.html,nge May2,1934
第六章电化学原理及其应用 一、选择题 1．下列电极反应中，溶液中的pH值升高，其氧化态的氧化性减小的是(C) A. Br2+2e = 2Br－ B. Cl2+2e=2Cl— C. MnO4—+5e+8H+=2Mn2++4H2O D. Zn2++2e=Zn 2．已知H2O2在酸性介质中的电势图为O2 0.67V H2O2 1.77V H2O，在碱性介质中的电势图为O2-0.08V H2O2 0.87V H2O，说明H2O2的歧化反应（C） A.只在酸性介质中发生 B.只在碱性介质中发生 C.无论在酸、碱性介质中都发生Ｄ.与反应方程式的书写有关 3．与下列原电池电动势无关的因素是Zn |Zn2+‖H+，H2 | Pt （B） A. Zn2+的浓度 B. Zn电极板的面积 C.H+的浓度 D.温度 4．298K时，已知Eθ（Fe3+/Fe）=0.771V，Eθ（Sn4+/Sn2+）=0.150V，则反应2Fe2++Sn4+=2Fe3++Sn2+的△r G mθ为（D）kJ/mol。 A. －268.7 B. －177.8 C. －119.9 D. 119.9 5．判断在酸性溶液中下列等浓度的离子哪些能共存（D） A Sn2+和Hg2+ B. SO32—和MnO4— C. Sn4+和Fe D. Fe2+和Sn4+ 已知Eθ(Hg2+/Hg)=0.851V，Eθ(Sn4+/Sn2+)=0.15V ，Eθ(MnO4—/Mn2+)=1.49V Eθ(SO42—/H2SO3)=1.29V ，Eθ(Fe2+/Fe)= —0.44V 6．已知下列反应在标准状态下逆向自发进行 Sn4++Cu = Sn2++Cu2+ Eθ(Cu2+/Cu)=(1) , Eθ(Sn4+/Sn2+)=(2) 则有（C） A. (1) = (2) B. (1)＜(2) C. (1)＞(2) D. 都不对 二、填空题 1．将下列方程式配平 3PbO2 + 2 Cr3+ + ____H2O___ ＝1Cr2O72—+ 3Pb2+ + __2H+___ (酸性介质) 2MnO2 + 3 H2O2 +__2OH-___ ＝2MnO4—+ ___4H2O______ （碱性介质）2．现有三种氧化剂Cr2O72—，H2O2，Fe3+，若要使Cl—、Br—、I—混合溶液中的I—氧化为I2，而Br-和Cl-都不发生变化，选用Fe3+最合适。(EθCl2/Cl-=1.36V, EθBr2/Br-=1.065V, EθI2/I-=0.535V) 3．把氧化还原反应Fe2++Ag+=Fe3++Ag设计为原电池，则正极反应为Ag++ e = Ag，负极反应为Fe3++e= Fe2+ ，原电池符号为Pt︱Fe3+(c1),Fe2+(c2)‖Ag+(c3)︱Ag。 4．在Ｍn++n e＝M(s)电极反应中，当加入Ｍn+的沉淀剂时，可使其电极电势值降低，如增加Ｍ的量，则电极电势不变 5．已知EθAg+/Ag=0.800V, K sp=1.6×10—10则Eθ（AgCl/Ag）= 0.222V。 6．已知电极反应Cu2++2e=Cu的Eo为0.347Ｖ,则电极反应2Cu - 4e =2Cu2+的Eθ值为0.347V 。7．用氧化数法配平下列氧化还原反应。 （1）K2Cr2O7＋H2S＋H2SO4K2SO4＋Cr2(SO4)3＋S＋H2O K2Cr2O7＋3H2S＋4H2SO4 =K2SO4＋Cr2(SO4)3＋3S＋7H2O
PREFACE TO FIFTEENTH EDITION This new edition,the?fth under the aegis of the present editor,remains the one-volume source of factual information for chemists,both professionals and students—the?rst place in which to“look it up”on the spot.The aim is to provide suf?cient data to satisfy all one’s general needs without recourse to other reference sources.A user will?nd this volume of value as a time-saverbecause of the many tables of numer ical data which have been especially compiled. Descriptive properties for a basic group of approximately4300organic compounds are compiled in Section1,an increase of300entries.All entries are listed alphabetically according to the senior pre?x of the name.The data for each organic compound include (where available)name,structural formula,formula weight,Beilstein reference(or if un-available,the entry to the Merck Index,12th ed.),density,refractive index,melting point, boiling point,?ash point,and solubility(citing numerical values if known)in water and various common organic solvents.Structural formulas either too complex or too ambig-uous to be rendered as line formulas are grouped at the bottom of each facing double page on which the entries appear.Alternative names,as well as trivial names of long-standing usage,are listed in their respective alphabetical order at the bottom of each double page in the regular alphabetical sequence.Another feature that assists the user in locating a desired entry is the empirical formula index. Section2on General Information,Conversion Tables,and Mathematics has had the table on general conversion factors thoroughly reworked.Similarly the material on Statis-tics in Chemical Analysis has had its contents more than doubled. Descriptive properties for a basic group of inorganic compounds are compiled in Section 3,which has undergone a small increase in the number of entries.Many entries under the column“Solubility”supply the reader with precise quantities dissolved in a stated solvent and at a given temperature. Several portions of Section4,Properties of Atoms,Radicals,and Bonds,have been signi?cantly enlarged.For example,the entries under“Ionization Energy of Molecular and Radical Species”now number740and have an additional column with the enthalpy of formation of the ions.Likewise,the table on“Electron Af?nities of the Elements, Molecules,and Radicals”now contains about225entries.The Table of Nuclides has material on additional radionuclides,their radiations,and the neutron capture cross sec-tions. Revised material for Section5includes the material on surface tension,viscosity,di-electric constant,and dipole moment for organic compounds.In order to include more data at several temperatures,the material has been divided into two separate tables.Ma-terial on surface tension and viscosity constitute the?rst table with715entries;included is the temperature range of the liquid phase.Material on dielectric constant and dipole vii
超级电容器的两个比电容计算公式？ 作者: Azrael-218(站内联系TA)发布: 2011-07-23 C=4it/amu(i:放电电流；t:放电时间；a:实际有用的电极材料百分含量；m:电极材料总质量；u:扣除电压降的那部分电压。 另外一个公式：C=it/amu. 这两个公式区别就是少乘一个4。这是什么情况啊？请各位虫友帮忙。。。谢谢了！ 举报删除此信息 liucheng200883(站内联系TA) 对于组装的完整超级电容器，C=4it/amu为计算单电极的比容量，C=it/amu计算整个电容器的比容量，并且后者一般是前者的4倍。对于对称的双电层电容，单电极和完整电容的电量是相同的，但是完整电容的电压是单电极的两倍，质量也是两倍 所以比容量只有1/4 个人愚见！！！仅供参考！ shang_qing(站内联系TA) 帖子真精彩! 已经收录到淘贴专辑《超级电容器》 杨仁立(站内联系TA) 626857楼 : Originally posted by liucheng200883 at 2011-07-23 22:34:33 对于组装的完整超级电容器，C=4it/amu为计算单电极的比容量，C=it/amu计算整个电容器的比容量，并且后者一般是前者的4倍。对于对称的双电层电容，单电极和完整电容的电量是相同的，但是完整电容的电压是单电极的两倍 ... 我还是没弄懂这个是怎么回事？？是前边是后边的四倍还是后边是前边的四倍呢？？请不吝赐教！！:P li_qqiong(站内联系TA) 楼主，这两个公式针对的电极体系是不一样的，有4倍的关系，有4的那个是利用3电极体系测出来数据计算的，另外一个是2电极体系的，也即是：Cspec-3E=4*Cspec-2E,请参考：Studies of activated carbons used in double-layer capacitors. wuanri(站内联系TA) 2楼 : Originally posted by liucheng200883 at 2011-07-23 22:34:33 对于组装的完整超级电容器，C=4it/amu为计算单电极的比容量，C=it/amu计算整个电容器的比容量，并且后者一般是前者的4倍。对于对称的双电层电容，单电极和完整电容的电量是相同的，但是完整电容的电压是单电极的两倍 ... 为什么全电容的电压是半电容电压的两倍？我觉得不对吧。 原因应该是全电容与单电极是半数关系，C总=C单*1/2； 但以全部质量计算出比电容量则是Cs总=C总/2m=C单/4m=Cs单*1/4； 所以全电容比电容是三电极测试的半电容的四分之一，但只是理论，实际上是有相差的。通过CV图与放电曲线计算的比容差别很大，什么原因？ 循环伏安变化的是电压，而响应的电流是随时间变化的;而充放电通常在恒电流下进行的，电压随之变化。因此，材料得失电子的速率不同，这是电极动力学的问题。 举个例子，你根据放电时间算的话，假设你沉积的活性物质重量是1mg，你的充放电电流大小为1mA，那么你的放电电流密度就是1A g-1，算成面积（假设沉积面积是2cm2）就是0.5mA cm-2，但如果你用积分做的话，换算成电流密度，很可能不是1A g-1或0.5mA cm-2，所以二者根本不具有可比性。一般是按照充放电曲线来算的，最好不要用积分曲线来算。循环伏安cyclic voltammetry (CV)
《让创新点亮课堂——一体化电化学综合创新实验装置》 厦门实验中学邹标赵丽佳 一、使用教材 本次说课内容是一节复习课，选自鲁科版高中化学选修4《化学反应原理》第一章第3节电化学的相关内容。 二、实验仪器 一体化电化学综合创新实验装置、烧杯、石墨电极。 三、实验创新点 1.通用性利用自主研发的一体化电化学综合创新实验装置能够用这一套装置完成课本上所有的有关电化学的实验。实现仪器的多功能性。 2.趣味性本装置为增加实验的趣味性，加入了小灯泡和音乐卡，激发学生学习的兴趣。 3.简约性整个操作简单方便节省时间。 4.直观性指针指示电流、数字显示电压，读数非常直观。 四、实验原理/实验设计思路 本节课是一节复习的实验探究课，学生对于原电池、电解池的反应原理理解的不够系统，学生主要是机械的记忆。教材上没有关于燃料电池的实验，只给了燃料电池的结构示意图。不够直观、比较抽象学生不容易理解。本节课利用自制的一体化电化学综合实验装置，能够更加直观、便捷、多功能。通过一体化电化学综合实验装置让学生亲自动手做有关的电化学实验，为学生学习电化学反应原理创设实验情景，帮助学生学习和理解反应原理。 五、实验教学目标 1.对原电池特别是燃料电池有深入的认识和理解。 2.通过实验提高学生的观察能力、动手能力和综合能力。 3.通过积极实验的探究，培养学生的创新能力。 六、实验教学内容 1.电解饱硫酸钠溶液和氢氧燃料电池。 2 .电解饱和氯化钠溶液和氢氯燃料电池。 3.甲醇燃料电池实验。 4.金属镁过氧化氢隔膜实验 5.水果电池实验。 七教学过程 1.介绍一体化学电化学综合创新实验装置 本套装置主要是由两个部分组成。左侧的部分是化学反应单元，这两根石墨电极上刻上螺旋槽，便于吸附更多气体。右侧为检测单元。检测单元又可以分为三个部分，最左边的是一个电流计，右边的是两个电压表。中间的电压表主要是电源的电压，最右边的电压表是测原电池的电压。最下边的两组接口分别是电源的输出端口和原电池的输出接口。整个装置可以看作是一个电源、电流表、电压表、电解池的整合体。
2017年中国化学奥林匹克竞赛浙江省预赛 一、选择题 (本题包括12小题，每小题4分，共48分。每小题只有一个选项符合题意) 1．2016年诺贝尔化学奖在瑞典皇家科学院揭晓，让·皮埃尔·索维奇，J·弗雷泽·斯托达特爵士和伯纳德·L·费林加三位科学家分享该奖，以表彰他们在“合成分子机器”方面的研 究。下列关于分子机器说法不正确 ．．．的是 A．“分子机器”尺寸小，可以依靠各种化学能、电能、光能等进行驱动，在纳米层次上控制单分子和多分子的运动 B．“分子机器”是通过分子和分子之间的共价键作用形成的结构固定的超分子组装体，再通过酸碱、离子、光、电等外界刺激，使分子之间发生相互运动，最终实现做功C．“分子机器”可以通过它的分子钳子与特定的病毒相结合，向肿瘤部位集中运输药物D．只要材料和环境条件具备，“分子机器”就能自动组装 2．化学与生活、社会发展息息相关，下列有关说法不正确 ．．．的是 A．“青蒿一握，以水二升渍，绞取汁”；屠呦呦改进提取青蒿素的方法，提取过程中发生了化学变化 B．“时气错逆，霾雾蔽日”，雾所形成的气溶胶能产生丁达尔效应 C．《中国诗词大会》不仅弘扬了中国传统文化，还蕴含着许多化学知识。例如刘禹锡诗句“千淘万漉虽辛苦，吹尽狂沙始到金”可以看出金性质稳定，可通过物理方法得到D．“外观如雪，强烧之，紫青烟起”。南北朝陶弘景对硝酸钾的鉴定过程中利用了焰色反应 3．离子液体（或称离子性液体）是指全部由离子组成的液体，如熔融NaCl、KOH等。室温附近呈液态的离子液体称为室温离子液体，其常见的阳离子有季铵盐离子、季鏻盐离子、咪唑盐离子、吡咯盐离子等，常见的阴离子有卤素离子、四氟硼酸根离子、六氟磷酸根离子等。离子液体具有许多传统溶剂无法比拟的独特性能，被广泛应用于化学研究的各个领域。下列 说法不正确 ．．．的是 A．离子液体在反应过程中可作为溶剂和催化剂，从而提高化学反应的速率 B．在使用含有重金属元素的离子液体时，要严格遵守安全守则，严禁用手直接触碰，同时佩戴防毒面具，防止离子液体易挥发而导致中毒 C．离子液体具有电导率高的特点，可作为电解质溶液应用于电化学研究 D．通过对离子液体的进一步研究，发现选择不同的阴阳离子可调节其对许多无机物、有机物的溶解度，在分离提纯物质方面具有良好的应用前景 4．下列说法正确的是 A．大分子化合物油脂在人体内水解为氨基酸和甘油等小分子才能被吸收 B．2017年2月，朝鲜第三代领导核心金正恩兄长金正男系神经毒剂“VX”中毒身亡，VX的键线式为： O C10H26PSNO2，无手性 N
1，电化学实际应用的范围及分类有哪些？ 答：(1)电合成无机物和有机物，例如氯气、氢氧化钠、高锰酸钾、己二腈、四烷基铅； (2)金属的提取与精炼，例如熔盐电解制取铝、湿法电冶锌、电解精练铜； (3)电池，例如锌锰电池、铅酸电池、镍硌电池、锂电池、燃料电池、太阳 能电池； (4)金属腐蚀和防护的研究，采取有效的保护措施，例如电化学保护、缓蚀剂保护； (5)表面精饰，包括电镀、阳极氧化、电泳涂漆等； (6)电解加工，包括电成型(电铸)、电切削、电抛磨； (7)电化学分离技术，例如电渗析、电凝聚、电浮离等应用于工业生产或废水处理； (8)电分析方法在工农业、环境保护、医药卫生等方面的应用。 3，试说明参比电极应具有的性能和用途。 答：参比电极是理想不极化电极，它应具备下列性能：应是可逆电极，其电极电势符合Nernst方程；参比电极反应应有较大的交换电流密度，流过微小的电流时电极电势能迅速恢复原状；应具有良好的电势稳定性和重现性等。 参比电极是指一个已知电势的接近于理想不极化的电极，参比电极上基本没有电流通过，用于测定研究电极(相对于参比电极)的电极电势。实际上，参比电极起着既提供热力学参比，又将工作电极作为研究体系隔离的双重作用。 4 , 试说明工作电极应具有的性能和用途。 答：工作电极(working electrode，简称WE)：又称研究电极，是指所研究的反应在该电极上发生。一般来讲，对工作电极的基本要求是：所研究的电化学反应不会因电极自身所发生的反比而受到影响，并且能够在较大的电位区域中进行测定；电极必须不与溶剂或电解液组分发生反应；电极面积不宜太大，电极表面最好应是均一、平滑的，且能够通过简单的方法进行表面净化等等。工作电极可以是固体，也可以是液体，各式各样的能导电的固体材料均能用作电极。通常根据研究的性质来预先确定电极材料，但最普通的“惰性”固体电极材料是玻碳(GC)、铂、金、银、铅和导电玻璃等。采用固体电极时，为了保证实验的重现性，必须注意建立合适的电极预处理步骤，以保证氧化还原、表面形貌和不存在吸附杂质的可重现状态。在液体电极中，汞和汞齐是最常用的工作电极，它们都是液体，都有可重现的均相表面，制备和保持清洁都较容易，同时电极上高的氢析出超电势提高了在负电位下的工作窗口，已被广泛用于电化学分析中。 5，试说明辅助电极应具有的性能及用途。 答：辅助电极和工作电极组成回路，使工作电极上电流畅通，以保证所研究的反应在工作电极上发生，但必须无任何方式限制电池观测的响应。由于工作电极发生氧化或还原反应时，辅助电极上可以安排为气体的析出反应或工作电极反应的逆反应，以使电解液组分不变，即辅助电极的性能一般不显著影响研究电极上的反应。但减少辅助电极上的反应对工作电极干扰的最好办法可能是用烧结玻璃、多孔陶瓷或离子交换膜等来隔离两电极区的溶液。为了避免辅助电极对测量到的数据产生任何特征性影响，对辅助电极的结构还是有一定的要求。如与工作电极相比，辅助电极应具有大的表面积使得外部所加的极化主要作用于工作电极上，辅助电极本身电阻要小，而且不容易极化，同时对其形状和位置也有要求。
Preface to the Dictionary of the English Language Samuel Johnson It is the fate of those who toil at the lower employments of life, to be rather driven by the fear of evil, than attracted by the prospect of good; to be exposed to censure, without hope of praise; to be disgraced by miscarriage, or punished for neglect, where success would have been without applause, and diligence without reward. Among these unhappy mortals is the writer of dictionaries, whom mankind have considered, not as the pupil, but the slave of science, the pioneer of literature, doomed only to remove rubbish and clear obstructions from the paths of Learning and Genius, who press forward to conquest and glory, without bestowing a smile on the
考点六辨析多池组合、突破电化学计算 李仕才 1．辨析多池组合 (1)直接判断：非常直观明显的装置，如燃料电池、铅蓄电池等在电路中，则其他装置为电解池。如图所示：A为原电池，B为电解池。 (2)根据电池中的电池材料和电解质溶液判断： 原电池一般是两种不同的金属电极或一种金属电极一个碳棒做电极；而电解池则一般都是两个惰性电极，如两个铂电极或两个碳棒。原电池中的电极材料和电解质溶液之间能发生自发的氧化还原反应，电解池的电极材料一般不能和电解质溶液自发反应。如图所示：B为原电池，A为电解池。 (3)根据电极反应现象判断： 在某些装置中根据电极反应或反应现象可判断电极，并由此判断电池类型。如图所示：若C 极溶解，D极上析出Cu，B极附近溶液变红，A极上放出黄绿色气体，则可知乙是原电池，D
是正极，C是负极；甲是电解池，A是阳极，B是阴极。B、D极发生还原反应，A、C极发生氧 化反应。 2．突破电化学计算 原则：电化学的反应是氧化还原反应，各电极上转移电子的物质的量相等，无论是单一电 池还是串联电解池，均可抓住电子守恒计算。 关键：a.电极名称要区分清楚；b.电极产物要判断准确； c．各产物间量的关系遵循电子得失守恒。 方法：(1)根据电子守恒计算 用于串联电路中阴阳两极产物、正负两极产物、相同电量等类型的计算，其依据是电路中 转移的电子数相等。 (2)根据总反应式计算 先写出电极反应式，再写出总反应式，最后根据总反应式列出比例式计算。 (3)根据关系式计算 根据得失电子守恒定律关系建立起已知量与未知量之间的桥梁，构建计算所需的关系式。 如以通过4 mol e－为桥梁可构建如下关系式： (式中M为金属，n为其离子的化合价数值) 该关系式具有总览电化学计算的作用和价值，熟记电极反应式，灵活运用关系式便能快速 解答常见的电化学计算问题。 注意在电化学计算中，还常利用Q＝I·t和Q＝n(e－)×N A××10－19 C来计算电路中通过 的电量。 [思维深化] 如图所示，图中装置甲是，乙是，若电路中有 mol电子转移，则Zn极溶 解，Cu极上析出 (标准状况)，Pt极上析出 mol，C极上析出Cu
电化学组合装置专题分析 将原电池和电解池结合在一起，综合考查化学反应中的能量变化、氧化还原反应、化学实验和化学计算等知识，是高考试卷中电化学部分的重要题型。该类题目的考查内容通常有以下几个方面：电极的判断、电极反应式的书写、实验现象的描述、溶液中离子的移动、pH 的变化以及电解质溶液的恢复、运用电子守恒处理相关数据等。 解答该类试题，透彻理解电化学原理是基础，准确判断电池种类是关键，灵活利用电子守恒是处理数据的法宝。具体可按以下三个步骤进行： 第一步：多池串联装置中电池类型的判断 (1)直接判断： 非常直观明显的装置，如燃料电池、铅蓄电池等在电路中，则其他装置为电解池。如下图中，A为原电池，B为电解池。 (2)根据电池中的电极材料和电解质溶液判断： 原电池一般是两种不同的金属电极或一个为金属电极另一个碳棒做电极；而电解池则一般都是两个惰性电极，如两个铂电极或两个碳棒。原电池中的电极材料和电解质溶液之间能发生自发的氧化还原反应，电解池的电极材料一般不能和电解质溶液自发反应。如下图中，B为原电池，A为电解池。 (3)根据电极反应现象判断： 在某些装置中根据电极反应或反应现象可判断电极，并由此判断电池类型，如图。 若C极溶解，D极上析出Cu，B极附近溶液变红，A极上放出黄绿色气体，则可知乙是原电池，D是正极， C是负极；甲是电解池， A是阳极，B是阴极。B、D极发生还原反应，
A、C极发生氧化反应。 第二步：利用相关概念进行分析判断 在确定了原电池和电解池后，利用有关概念作分析和判断，如电极的判断、电极反应方程式的书写、实验现象的描述、溶液中离子的移动方向、pH的变化及电解质溶液的恢复等。只要按照各自的规律分析即可。 第三步：串联装置中的数据处理 原电池和电解池综合装置的有关计算的根本依据就是电子转移的守恒，分析时要注意两点：①串联电路中各支路电流相等；②并联电路中总电流等于各支路电流之和。在此基础上分析处理其他各种数据。 上图中，装置甲是原电池，装置乙是电解池，若电路中有0.2 mol 电子转移，则Zn极溶解6.5 g，Cu极上析出H22.24 L(标准状况)，Pt极上析出Cl20.1 mol，C极上析出Cu 6.4 g。甲池中H＋被还原，产生H2，负极Zn氧化生成ZnSO4溶液，pH变大；乙池中是电解CuCl2溶液，由于Cu2＋浓度的减小使溶液pH微弱增大，电解后再加入适量CuCl2固体可使溶液复原。 【典例解析】 1．烧杯A中盛放0.1 mol/L的H2SO4溶液，烧杯B中盛放0.1 mol/L的CuCl2溶液(两种溶液均足量)，组成的装置如图所示。下列说法不正确的是( ) A．A为原电池，B为电解池 B．A为电解池，B为原电池 C．当A烧杯中产生0.1 mol气体时，B烧杯中产生气体的物质的量也为0.1 mol D．经过一段时间，B烧杯中溶液的pH增大 解析：选B 构成A装置的是活泼性不同的两电极，两电极均浸在电解质溶液中，两极形成了闭合回路，所以A装置为原电池装置，且A装置为B装置提供电能。A装置中的电极反应式：正极：2H＋＋2e－===H2↑，负极：Fe－2e－===Fe2＋。B装置中的电极反应式：阴极：Cu2＋＋2e－===Cu，阳极：2Cl－－2e－===Cl2↑。装置B是电解氯化铜溶液，铜离子浓度减小，
高中化学竞赛专题考试 氧化还原反应、电化学 （本卷共130分。考试时间3小时） 班级： 姓名： 1.008 Zr Nb Mo T c Ru Rh Pd Ag Cd In S n S b T e I Hf T a W Re Os Ir Pt Au Hg T l Pb Bi Po At Ac-Lr H Li Be B C N O F Na Mg Al S i P Cl S K Ca S c T i V Cr Mn Fe Co Ni Cu Zn G a G e As S e Br Rb Cs Fr S r Ba Ra Y La Lu -6.9419.01222.9924.31 39.1040.0885.4787.62132.9137.3[223][226]44.9647.8850.9452.0054.9455.8558.9363.5558.6965.3910.8126.9869.7212.0128.0972.61114.8204.4118.7207.2112.4200.6107.9197.0106.4195.1102.9192.2101.1190.298.91186.295.94183.992.91180.991.22178.588.9114.0116.0019.0030.9774.92121.8209.032.0778.96127.6[210][210][210]126.979.9035.454.003 20.18 39.9583.80 131.3 [222]He Ne Ar Kr Xe Rn 相对原子质量 Rf Db Sg Bh Hs Mt 一 选择题（每题只有1个正确选项，每题1.5分，共30分。） 1、医学专家提出人体中细胞膜内的葡萄糖和细胞膜外的富氧液体与细胞膜构成了微型的生物原电池，有关该原电池的下列说法中，正确的是 （ ） A.正极的电极反应可能是O 2＋4e →2O 2－ ，且正极附近溶液的pH 值升高。 B.正极的电极反应可能是O 2＋2H 2O ＋4e →4OH － ，且正极附近溶液的pH 值降低。 C.负极反应主要是C 6H 12O 6－12e →6CO ＋12H ＋ ，且负极附近溶液的pH 值降低。 D.负极反应主要是C 6H 12O 6＋12OH － －12e →6CO 2＋6H 2O ，且负极附近溶液pH 值降低。 2在配平P 4+CuSO 4+H 2O →Cu 3P+H 3PO 4+ H 2SO 4时，H 2O 前面的化学计量数应为 （ ） A.60 B.70 C.85 D.96 3 在配平的下列反应中， □H 3AsO 4(aq)+□Zn(s)+□H +(aq)+□H 2O(aq)→□AsH 3 (g) +□Zn(H 2O)42+(aq)， H 2O 前面的系数为 A.8 B.12 C.16 D.20 4某温度下，将Cl 2通入NaOH 溶液，反应后得到NaCl 、NaClO 、NaClO 3的混合物。经测定ClO -与ClO 3-的浓度之比为1:3，则Cl 2与NaOH 溶液反应时，被还原的氯元素与被氧化的氯元素的物质的量之比为 A.21:5 B.11:3 C. 3:1 D.4:1 5．2003年2月1日，美国哥伦比亚号航天飞机在返回地面的途中坠毁，举世震惊。该航天飞机用铝粉和高氯酸铵(NH 4C1O 4)的混合物为固体燃料，点燃时铝粉氧化放热，引发高氯酸铵反应，产生N 2、Cl 2、O 2和H 20并放出大量的热。下列对此反应的叙述中正确的是 ( ) A ．上述反应瞬间产生大量的高温气体推动飞机飞行 B ．在反应中高氯酸铵只起氧化剂作用 C ．其方程式可表示为2 NH 4C1O 4=N 2↑+4H 20+C12↑ +O 2↑ D ．上述反应中反应物的总能量小于生成物的总能量 6 三聚氰酸[C 3N 3(OH)3]可用于消除汽车尾气中的NO 2。其反应原理为： C 3N 3(OH)3?→? ?HNCO HNCO ＋NO 2?→?? N 2＋CO 2＋H 2O 下列说法中正确的是 A. C 3N 3(OH)3与HNCO 为同一种物质 B. HNCO 是一种很强的氧化剂 C . 反应中NO 2是还原剂 D .1mol NO 2在反应中转移4mol 电子 7. 2004年美国圣路易斯大学研制了一种新型的乙醇电池，它用磺酸类质子溶剂，在200o C 左右时供电，乙醇电池比甲醇电池效率高出32倍且更安全。 电池总反应为：C 2H 5OH +3O 22CO 2 +3H 2O ， 电池示意如右图，下列说法不正确．．．的是 A.a 极为电池的负极 B.电池工作时电流由b 极沿导线经灯泡再到a 极
应用电化学，辉卢文庆 全书思考题和习题 第一章习题解答： 1试推导下列各电极反应的类型及电极反应的过程。 (1)++ →+242Ce e Ce 解：属于简单离子电迁移反应，指电极/溶液界面的溶液一侧的氧化态物种4Ce + 借助于电极得到电子，生成还原态的物种2Ce + 而溶解于溶液中，而电极在经历氧化-还原后其物理化学性质和表面状态等并未发生变化， (2) -→++OH e O H O 44222 解：多孔气体扩散电极中的气体还原反应。气相中的气体2O 溶解于溶液后，再扩散到电极表面，然后借助于气体扩散电极得到电子，气体扩散电极的使用提高了电极过程的电流效率。 (3) Ni e Ni →++22 解：金属沉积反应。溶液中的金属离子2Ni + 从电极上得到电子还原为金属Ni ，附着于电极表面，此时电极表面状态与沉积 前相比发生了变化。 (4) -+→++OH s MnOOH O H e s MnO )()(22 解：表面膜的转移反应。覆盖于电极表面的物种(电极一侧)经过氧化-还原形成另一种附着于电极表面的物种，它们可能是氧化物、氢氧化物、硫酸盐等。 (5)2)(22OH Zn e OH Zn →-+-；--→+242])([2)(OH Zn OH OH Zn 解：腐蚀反应：亦即金属的溶解反应，电极的重量不断减轻。即金属锌在碱性介质中发生溶解形成二羟基合二价锌络合物，所形成的二羟基合二价锌络合物又和羟基进一步形成四羟基合二价锌络合物。 2．试说明参比电极应具有的性能和用途。 参比电极(reference electrode ，简称RE)：是指一个已知电势的接近于理想不极化的电极，参比电极上基本没有电流通过，用于测定研究电极(相对于参比电极)的电极电势。 既然参比电极是理想不极化电极，它应具备下列性能：应是可逆电极，其电极电势符合Nernst 方程；参比电极反应应有较大的交换电流密度，流过微小的电流时电极电势能迅速恢复原状；应具有良好的电势稳定性和重现性等。 不同研究体系可以选择不同的参比电极，水溶液体系中常见的参比电极有：饱和甘汞电极(SCE)、Ag/AgCl 电极、标淮氢电极(SHE 或NHE)等。许多有机电化学测量是在非水溶剂中进行的，尽管水溶液参比电极也可以使用，但不可避免地会给体系带入水分，影响研究效果，因此，建议最好使用非水参比体系。常用的非水参比体系为Ag/Ag+(乙腈)。工业上常应用简易参比电极，或用辅助电极兼做参比电极。在测量工作电极的电势时，参比电极的溶液和被研究体系的溶液组成往往不—样，为降低或消除液接电势，常选用盐桥；为减小末补偿的溶液电阻，常使用鲁金毛细管。 3．试描述双电层理论的概要。 解：电极/溶液界面区的最早模型是19世纪末Helmholtz 提出的平板电容器模型(也称紧密层模型)，他认为金属表面过剩的电荷必须被溶液相中靠近电极表面的带相反电荷的离子层所中和，两个电荷层间的距离约等于离子半径，如同一个平板电容器。这种
人教版高中化学实验装置图汇总（必修一） 章节名 称实验名称实验原理 实验装置仪器药品清单备注 第一章第一节： 化学实验基本方法过滤 固体与液体混合 物的分离 仪器：漏斗、烧 杯、玻璃板、铁 架台（带铁圈）、 滤纸 药品：固液混合 物 操作要 点：“一 贴二低 三靠”蒸发 分离溶剂中的溶 质 仪器：蒸发皿、 酒精灯、玻璃 棒、铁架台 药品：食盐水溶 液 注意： 蒸发过 程中要 不断搅 拌，在 加热至 有大量 固体析 出时要 用余温 加热 蒸馏 混合物中各组分 的沸点不同 仪器：蒸馏烧 瓶、酒精灯、铁 架台、冷凝管、 锥形瓶 药品：液体混合 物 加热前 一定要 检验装 置的气 密性 萃取 物质在互不相容 的溶剂里的溶解 度不同，用一种溶 剂把物质从它与 另一种溶剂所组 成的溶液里提取 出来 分液漏斗、烧 杯、铁架台(带 铁圈) 进行分 液操作 之前一 定要进 行检漏
第一章 第二节：化学计量在实验中的应用配制一定 量浓度的 溶液 C=n/V 仪器：容量瓶、 量筒、烧杯、玻 璃棒、胶头滴 管、托盘天平 药品：氯化钠固 体、蒸馏水 容量瓶 在使用 之前一 定要检 漏 第二章 第一节：物质的分类丁达尔效 应 当一束光线透过 胶体，从入射光的 垂直方向可以观 察到胶体里出现 的一条光亮的“通 路” 仪器：激光笔、 烧杯 药品：某种胶体 第三章 第一节：金属的化学性 质加热金属 钠 钠受热后，与氧气 剧烈反应，发出黄 色火焰，生成一种 淡黄色固体，过氧 化钠 仪器：小刀、铁 架台（带铁圈）、 酒精灯药品： 金属钠 注意安 全 金属钠和 水的反应 活泼金属和水的 剧烈反应 仪器：小刀、烧 杯 药品：蒸馏水、 金属钠、酚酞 注意观 察实验 现象 铝与盐酸 和氢氧化 钠溶液的 反应 铝是两性金属，既 能和酸反应又能 和碱反应 仪器：试管、架 子 药品：盐酸溶 液、氢氧化钠溶 液 注意检 查生成 的气体 第三章 第二节：几种重要的金属化合 物过氧化钠 和水的反 应 过氧化钠可以与 水反应生成氧气 仪器：试管、火 柴 药品：过氧化 钠、蒸馏水、 注意检 验生成 的气体
电化学 胡征善 电化学是电与化学准确地说是电子与氧化还原反应的结晶。氧化还原反应有电子的转移而产生电——电池，电能使某些化学物种有电子得失而发生氧化还原反应——电解。 能量转化 太阳能、化学能、电能的互相转化 氧化还原反应 1、概念 2、氧化还原性的比较 电解质溶（熔）液 1.离子迁移（盐桥与交换膜） 2.n (离子)、V (aq)、pH 变化 3.离子可在多孔的固体中定向移动 应用 1、新型化学电源的开发 2、物质制备(合成)的新方法 3、环境化学(废气、废液的处理) 4、金属的电化腐蚀与电化防腐 负阳氧，正阴还内离移，外电流 原电池必须ΔG<0 电解、利用光能可使ΔG>0被迫发生 强者优先 电极反应与离子方程式 电化学包括电池和电解。电池即在两电极上自发发生氧化反应和还原反应而产生电流(电动势ε>0)。电解即是在直流电的作用下在两电极上发生氧化反应和还原反应。 负极（—）——电位低 发生氧化反应 1．活泼的金属——电极失电子而溶解 2．燃料——燃料失电子 燃料电池的电极可以相同，但要求电极多孔(表面积大)——吸附能力强；具有催化作用 正极（+）——电位高 发生还原反应 1．①较不活泼的金属、石墨 ——导体 ②氧化性较强的难溶性氧化物PbO 2、Ag 2O 或 Ag 2O 2、NiO(OH)——电极本身得电子 2．氧化性气体[如氧气(空气)、氯气等]——氧化性气体得电子 e — I 电解质溶(熔)液 A
外电路的电子流动与电解质溶(熔)液中离子迁移的关系： 例如： 通过溶液每一截面: n(H+)+n(Cl—)=x mol 2n(Cu2+)+n(Cl—)=x mol 若有阴或阳离子交换膜： 一、电池(化学电源) 电池(化学电源)有多种不同的分类。如：一次电池和二次电池；酸性电池、碱性 电解质溶(熔)液 e—e— 电池的电动势大于电解质溶(熔)液 的分解电压，电解才能得以实现 e—e— 阴极——接电池的负极 （多电子的电极） 发生还原反应 金属或石墨——导体 氧化性材料——得电子 阳极——接电池的正极 （缺电子的电极） 发生氧化反应 1．惰性电极(Au、Pt、石墨)——导 体。溶(熔)液中阴离子失电子 2．活泼电极 电极本身失电子溶解
1、何谓电毛细曲线？何谓零电荷电势？由lippman公式可进一步得到界面双电层得微分电容Cd，请给出Cd得数学表达式。 答：①将理想极化电极极化至不同电势（Φ），同时测出相应得界面张力（σ值），表征Φ-6关系得曲线为“电毛细曲线”。②“零电荷电势”就是指σ-Φ曲线上最高点处dσ/dΦ=0即q=0（表面不带有剩余电荷）相应得电极电势，用Φ 0表示。③由lippman公式：q=-（dσ/dΦ)μ 1 , μ 2 ,、、、μ i ;及Cd=dq/dΦ得Cd=-d2σ/dΦ2 2、何谓电化学极化？产生极化得主要原因就是什么？试分析极化在电解工业（如氯碱工业）﹑电镀行业与电池工业得利弊。 答：①电化学极化就是指外电场作用下，由于电化学作用相对于电子运动得迟缓性改变了原有得电偶层而引起电极电位变化。（即电极有净电流通过时，阴、阳电流密度不同，使平衡状态受到了破坏，而发生了电极电位得“电化学极化”）。 ②原因：电化学反应迟缓、浓差极化。③从能量角度来瞧，极化对电解就是不利得；超电势越大，外加电压越大，耗能大。极化在电镀工业中就是不利得，氢在阴极上析出就是不可避免得副反应，耗能大，但同时使阴极上无法析出得金属有了析出得可能。极化使电池放电时电动势减少，所做电功也减小，对电池工业不利 3、参比电极需选用理想极化电极还就是不极化电极？目前参比电极有那些类型？选择参比电极需考虑什么？ 答：①参比电极选用理想不极化电极。②类型：标准氢电极，饱与甘汞电极，Ag/Agcl电极，Hg/HgO/OH-电极。③考虑得因素：电极反应可逆，稳定性好，重现性好，温度系数小以及固相溶解度小，与研究体系不反应 4、零电荷得电势可用哪些方法测定？零电荷电势说明什么现象？能利用零电荷电势计算绝对电极电位吗？ 答：①电毛细法与微分电容法。②零电荷电势表明了“电极/溶液”界面不会出现由于表面剩余电荷而引起得离子双电层现象；③不能将此电势瞧成相间电势得绝对零点，该电势也就是在一定参比电极下测得得，所以不能用于计算绝对电极电位。 5、为什么卤素离子在汞电极上吸附依F﹤Cl﹤I 得顺序而增强，特性吸附在电毛细曲线与微分电容曲线上有何表现？ 答：①卤素离子为表面活性物质，阴离子吸附主要发生在比零电荷电势更正得电势范围，由于F-、cl- 、I-离子半径依次增大，可极化度增大，吸附能力增强，所以在汞电极上，I->cl->F-、②特性吸附在两种曲线上得左半支曲线不同，零电荷 电势负移。 6、何谓非稳态扩散？其初始条件与一个边界条件就是什么？另一边界条件由极化条件决定。答：①非稳态扩散：在电化学反应开始阶段，由于反应粒子浓度变化幅度较小，液相传质不足，粒子被消耗，此时浓度极化处于发展阶段，称之为传质过程得非稳态阶段②初始条件：C i（x,0）=C i0 开始电极前扩散粒子完全均匀分布在液相中。边界条件：C i（∞，t）=C i0，无穷远处不出现浓度极化。③另一边界条件：极化条件 7、溶液中有哪几种传质方式，产生这些传质过程得原因就是什么？ 答：对流、扩散、电迁移。①对流：由于流体各部分之间存在浓度或温度差或者外部机械作用力下所引起；②扩散：由于某一组分存在浓度梯度，粒子由高浓度向低浓度转移；③电迁移：在外电场作用下，液相中带电粒子作定向移动。8、稳态扩散与非稳态扩散得特点就是什么，可以用什么定律来表示？ 答：①稳态扩散：扩散粒子得浓度只与距离有关，与时间无关。用Fick第一定律表示，J表示扩散流量。②非稳态扩散：扩散粒子得浓度同时就是距离与时间得函数。用Fick第二定律 9、说明标准电极反应速度常数k S与交换电流密度i0得物理意义，并比较两者得区别。 答：①k S：当电极电势为反应体系得标准平衡及反应粒子为单位浓度时，电极反应进行得速率（md/s）。i0：反应在平衡电势下得电流密度，即有i0=i a=i k②相同点：数值越大，表示该反应得可逆性越强。不同点：k S与浓度无关，i0与反应体系各种组分得浓度有关。 10、为什么有机物在电极上得可逆吸附总就是发生在一定得电位区间内？ 答：越正得电势，有机物易被氧化；电势越负，易被还原，因此其可逆吸附发生在平衡电势附近值，即一定得电位区间内。 11、试说明锂离子电池得正极与负极材料就是何物质？为什么其溶剂要用非水有机溶剂? 锂离子电池比一般得二次电池具有什么特点？ 答：①正极：主要就是嵌锂化合物，包括三维层状得LiCoO 2 ,LiNiO 2 ,三维得TiO 2 。负极：主要就是碳素材料，如石墨、碳纤维。②锂遇水反应生 成H 2 ，可能有爆炸得危险，所以要用非水有机溶