Georg Job Regina Rüffl er Physical Chemistry from a Diff erent Angle Introducing Chemical Equilibrium, Kinetics and Electrochemistry by Numerous Experiments Physical Chemistry from a Different Angle ThiSisaFMBlankPage Georg Job • Regina Ru¨ffler Physical Chemistry from a Different Angle Introducing Chemical Equilibrium, Kinetics and Electrochemistry by Numerous Experiments GeorgJob ReginaRu¨ffler JobFoundation JobFoundation Hamburg Hamburg Germany Germany TranslatedbyRobinFuchs,GETS,Winterthur,Switzerland HansU.Fuchs,ZurichUniversityofAppliedSciencesatWinterthur,Switzerland ReginaRu¨ffler,JobFoundation,Hamburg,Germany BasedonGermanedition“PhysikalischeChemie”,ISBN978-3-8351-0040-4,publishedby SpringerVieweg,2011. Exercisesaremadeavailableonthepublisher’swebsite: http://extras.springer.com/2015/978-3-319-15665-1 BycourtesyoftheEduard-Job-FoundationforThermo-andMatterdynamics ISBN978-3-319-15665-1 ISBN978-3-319-15666-8 (eBook) DOI10.1007/978-3-319-15666-8 LibraryofCongressControlNumber:2015959701 SpringerChamHeidelbergNewYorkDordrechtLondon ©SpringerInternationalPublishingSwitzerland2016 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpart of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation,broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,andtransmissionor informationstorageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilar methodologynowknownorhereafterdeveloped. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publicationdoesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexempt fromtherelevantprotectivelawsandregulationsandthereforefreeforgeneraluse. Thepublisher,theauthorsandtheeditorsaresafetoassumethattheadviceandinformationinthisbook arebelievedtobetrueandaccurateatthedateofpublication.Neitherthepublishernortheauthorsorthe editorsgiveawarranty,expressorimplied,withrespecttothematerialcontainedhereinorforanyerrors oromissionsthatmayhavebeenmade. Printedonacid-freepaper Springer International Publishing AG Switzerland is part of Springer Science+Business Media (www.springer.com) Preface Experience has shown that two fundamental thermodynamic quantities are espe- cially difficult to grasp: entropy and chemical potential—entropy S as quantity associatedwithtemperatureTandchemicalpotentialμasquantityassociatedwith the amount of substance n. The pair S and T is responsible for all kinds of heat effects, whereas the pair μ and n controls all the processes involving substances suchaschemicalreactions,phasetransitions,orspreadinginspace.Itturnsoutthat Sandμarecompatiblewithalayperson’sconception. In this book, a simpler approach to these central quantities—in addition to energy—is proposed for the first-year students. The quantities are characterized bytheirtypicalandeasilyobservableproperties,i.e.,bycreatingakindof“wanted poster” for them. This phenomenological description is supported by a direct measuringprocedure,amethodwhichhasbeencommonpracticeforthequantifi- cationofbasicconceptssuchaslength,time,ormassforalongtime. The proposed approach leads directly to practical results such as the predic- tion—baseduponthechemicalpotential—ofwhetherornotareaction runsspon- taneously.Moreover,thechemicalpotentialiskeyindealingwithphysicochemical problems. Based upon this central concept, it is possible to explore many other fields. The dependence of the chemical potential upon temperature, pressure, and concentration is the “gateway” to the deduction of the mass action law, the calculation of equilibrium constants, solubilities, and many other data, the con- struction of phase diagrams, and so on. It is simple to expand the concept to colligative phenomena, diffusion processes, surface effects, electrochemical pro- cesses, etc. Furthermore, the same tools allow us to solve problems even at the atomic and molecular level, which are usually treated by quantum statistical methods. This approach allows us to eliminate many thermodynamic quantities thataretraditionallyusedsuchasenthalpyH,GibbsenergyG,activitya,etc.The usage of these quantities is not excluded but superfluous in most cases. An opti- mized calculus results in short calculations, which are intuitively predictable and canbeeasilyverified. v vi Preface Because we choose in this book an approach to matter dynamics directly by usingthechemicalpotential,applicationoftheconceptofentropyislimitedtothe descriptionofheateffects.Still,entropyretainsitsfundamentalimportanceforthis subjectandiscorrespondinglydiscussedindetail. Thebookdiscussestheprinciplesofmatterdynamicsinthreeparts, • Basicconceptsandchemicalequilibria(statics), • Progressionoftransformationsofsubstancesintime(kinetics), • Interactionofchemicalphenomenaandelectricfields(electrochemistry) and gives at the same time an overview of important areas of physical chemistry. Becausestudentsoftenregardphysicalchemistryasveryabstractandnotusefulfor everyday life, theoretical considerations are linked to everyday experience and numerousdemonstrationexperiments. We addressthisbooktoundergraduatestudentsincourseswherephysicalchem- istryisrequiredinsupportbutalsotobeginnersinmainstreamcourses.Wehaveaimed tokeeptheneedsofthisaudiencealwaysinmindwithregardtoboththeselectionand the representation of the materials. Only elementary mathematical knowledge is necessary for understanding the basic ideas. If more sophisticated mathematical tools are needed, detailed explanations are incorporated asbackground information (characterizedbyasmallerfontsizeandindentation).Thebookalsopresentsallthe materialrequiredforintroductorylaboratorycoursesinphysicalchemistry. Exercisesaremadeavailableonthepublisher’swebsite.Astudentmanualwith commentedsolutionsisinpreparation.Detaileddescriptionsofaselectionofdem- onstrationexperiments(partlywithcorrespondingvideosclips)canbefoundonour web site (www.job-foundation.org; see teaching materials); the collection will be continuouslyextended.Furtherinformationtothetopicsofquantumstatisticsandthe statisticalapproachtoentropy,which wouldgobeyondthescopeofthisbook, can alsobecalleduponthefoundation’shomepage. Preface vii { We would particularly like to thank Eduard J. Job , the founder of the Job Foundation, who always supported the goals of the foundation and the writing of thecurrentbook,withgreatpersonalcommitment.Becauseefficientapplicationof thermodynamics played an important role in his work as an internationally suc- cessful entrepreneur in the field of fire prevention and protection, he was particu- larlyinterestedinasimplifiedapproachtothermodynamicsallowingforfasterand moresuccessfullearning. Wegratefullyacknowledgetheconstantsupportandpatienceoftheboardofthe Job foundation. Additionally, we would like to thank the translators of the book, Robin Fuchs and Prof. Hans U. Fuchs, for their excellent collaboration, and Dr.SteffenPaulyandBeateSiekatSpringerfortheiradviceandassistance.Finally, wewouldliketoexpressourgratitudetocolleagueswhogavetheiradviceonthe GermaneditionandrevieweddraftchaptersoftheEnglishedition:Prof.Friedrich Herrmann,Prof.Gu¨nterJakobLauth,Prof.FriedhelmRadandt,andDr.Uzodinma Okoroanyanwu. Wewouldbeverygratefulforanycontributionsorsuggestionforcorrectionsby thereaders. Hamburg,Germany GeorgJob November2014 ReginaRu¨ffler ThiSisaFMBlankPage List of Used Symbols In the following, the more important of the used symbols are listed. The number added in parentheses refers to the page where the quantity or term if necessary is described indetail. Special characters as prefix (j, Δ, Δ , Δ , ...) were omitted R s!l whenorderingthesymbolsalphabetically. Greeklettersinalphabeticalorder: ΑαΒβΓγΔδΕεΖζΗηΘθϑIιKκΛλMμΝvΞξΟoΠπΡρΣσςΤτΥυΦφΧχ ΨψΩω. Roman A,B,C,... SubstanceA,B,C,... jA,jB,... DissolvedinA,inB,...(240) Ad Acid(188) a,ja Amorphous(19)(alsosubscriptedorsuperscripted) Bs Base(188) C Catalyst(462) c,jc Crystalline(19)(alsosubscriptedorsuperscripted) d,jd Dissolved(19)(alsosubscriptedorsuperscripted) E Enzyme(466) e,e(cid:2) Electron(s)(7,553)(alsosubscripted) e Eutectic(367)(alsosubscriptedorsuperscripted) F Foreignsubstance(320) g,jg Gaseous(19)(alsosubscriptedorsuperscripted) J Ion,unspecific(533) l,jl Liquid(19)(alsosubscriptedorsuperscripted) M Mixture(homogeneous)(346) M Mixture(heterogeneous)(348) Me Metal,unspecific(533) m,jm Metallic(conductingelectrons)(553)(alsosubscriptedor superscripted) Ox Oxidizingagent(537) ix