chemistry 218 - athabascau.ca20 electrochemistry week 7 weeks 11-12 weeks 13-15 21 nuclear chemistry...

Chemistry 218Chemical Principles II

Student Manual

Note: This StudentManualwas prepared primarily for individualized-studystudents. Studentswho are taking this coursewith seminar support or througha co-operating institution should be aware that some of the informationwillnot apply in their situation. In case of doubt, please ask your tutor or seminarleader about any problems thatmight arise. Further clarification can beobtained from the course professor.

Athabasca Universitya

Course Team

Author: Lawton ShawEditor: Jonathan LeggoCover Design: Jingfen ZhangVisual Presentation: DigitalMedia TechnologyUnit

This course replacesChemistry 218: Chemical Principles II, whichwas preparedfor Athabasca University by the following course team:

Author: Dietmar KennepohlEditor: ErnaDominey

This course includes learning objectives and othermaterials developed byDr. Arthur Last for the original version of Athabasca University’sintroductory chemistry course.

The cover image shows the three types of carbon nanotubes: zigzag (top), chiral(bottom left), and armchair (bottom right).

Image:Michael Ströck, February 1, 2006. RetrievedDecember 2006 fromhttp://commons.wikimedia.org/wiki/Image:Types_of_Carbon_Nanotubes.png

This image is reproduced, withmodifications, under the licence below. Please notethat the licence applies to the cover image only:

Permission is granted to copy, distribute and/ormodify this document under theterms of the GNUFreeDocumentation License, Version 1.2 or any later versionpublished by the Free Software Foundation; with no Invariant Sections, noFront-Cover Texts, and no Back-Cover Texts. A copy of the licence is included in thesection entitled ”GNUFreeDocumentation Licence”.[http://commons.wikimedia.org/wiki/Commons:GNU_Free_Documentation_License]

Every effort has been taken to ensure that thesematerials complywith therequirements of copyright clearances and appropriate credits. AthabascaUniversitywill attempt to incorporate in future printings any correctionswhich are communicated to it.

The inclusion of anymaterial in this publication is strictly in accordwith theconsents obtained andAthabasca University does not authorize or license anyfurther reproduction or usewithout the consent of the copyright holder.

Athabasca University 1998, 2000, 2001, 2004, 2007Revised EditionAll rights reservedPrinted in Canada

CMID 546741

Contents

TheCourse 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ThemyAUPortal 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Your Student IDNumber 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Freedomof Information and Protection of Privacy 2. . . . . . . . . . . . . . . . . . . . .

TheAthabasca University Calendar 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CourseMaterials 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

OtherMaterials 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CourseWebsite 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Laboratories 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Course Tutor 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Course Professor 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Services to Students 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Library Services 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SupplementaryMaterials 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Study Strategies 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Assessment 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Tutor-markedAssignments 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Applying for andWriting Examinations 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Plagiarism andAcademicHonesty 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Transferring Credit 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Transcripts 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Applying for Extensions 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CourseOutline and Study Schedules 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sample Examinations 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

AppendixA: Answer Keys 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chemistry 218/StudentManual 1

The Course

Welcome toChemistry 218: Chemical Principles II, the second of two three-credit courses in general chemistry,which beganwithChemistry 217: ChemicalPrinciples I. These two courses provide an essential foundation for furtherstudies in chemistry, biology, physics, earth sciences, or environmentalscience. They can also be used towards fulfilling the entry requirements formedicine, pharmacy, food science, agricultural science, forestry, and otherprograms.Wherever possible, the coursematerial discusses the relevance ofchemistry to the contemporaryworld. Laboratory exercises illustratemanyof the theoretical concepts covered in the course, and give students anopportunity to develop practical laboratory skills. Together,Chemistry 217andChemistry 218 are equivalent to an eight-month, two-semester course at atraditional university.

Topics inChemistry 218 include chemical kinetics, chemical equilibria, acid-base and aqueous equilibria, thermodynamics, electrochemistry, nuclearchemistry, and a survey of descriptive chemistry. The course outline, given inthe “CourseOutline and Study Schedules” section of thismanual, provides amore detailed description.

This StudentManual contains essential information about the design of thecourse and the coursematerials. It also contains sample examinations,tutor-marked assignments, and information about the procedures youshould follow to obtain themaximumbenefit fromyour studies. Before youbegin towork onChemistry 218, please read this StudentManual throughcarefully. If you have any questions about the course itself, or how to proceedwith your studies, please contact your tutor or the course professor.

The myAU Portal

MyAU is a personalized portal to theUniversity throughwhich you canquickly access information that is relevant to you, including onlinecomponents of your courses. ThroughmyAU, you can viewpersonalinformation, such as library accounts, assignmentmarks and course grades,and take care of administrativematters, such as booking examinations,submitting assignments, applying for extensions, registering for courses, andso on. Athabasca Universitywill also communicate directlywith youthroughmyAU. Check theMessage Centre on yourmyAUhome page bothfor general information and formail addressed specifically to you.

To login at

http://my.athabascau.ca/

enter your student ID number and passwordwhere requested. If you arehaving browser difficulties or you need help, refer tomyAUHelp at

http://www.athabascau.ca/uportal/help/index.php

2 Chemical Principles II

Your Student ID Number

In contacts with your tutor, on assignments, or in any correspondence orother contactwith theUniversity, you are asked to provide your student IDnumber. Record this number in the space below.Having your student IDnumberwill helpUniversity personnel process requests, grades, andadministrativemattersmore quickly.

Student ID number:

Note: It is important thatwe receive notification of any change of address ortelephone number. Please inform theOffice of the Registrarwhenever such achange occurs. You can update your contact information through yourmyAUportal, or use the form included in the coursematerials package. In addition,you should send change-of-address cards to your tutor and to the courseprofessor, so that your student files can be kept up-to-date.

Freedom of Information and Protection of Privacy

The personal information and records collected andmaintained byAthabascaUniversity as a result of a student’s registration in this course, such ascompleted assignments and examinations, electronic communications, andcorrespondence, are subject to University policies and the privacy and accessprovisions of Alberta’s Freedom of Information and Protection of Privacy Act.

The Athabasca University Calendar

BecauseAthabasca University’s policies, practices, and procedures changeover time, some of the information in this StudentManualmay lose itscurrency between course revisions.We therefore recommend that studentsrefer to the currentAthabasca University Calendar on important issuesconcerningUniversity policies, procedures, and practices. In the event ofany discrepancy between the printed version of theCalendar and the officialWeb-basedCalendar, theWeb-based versionwill be binding.


Course Materials

The package you received should include each of the items listed below. Ifanything ismissing fromyour package, please contact the CourseMaterialsdivision of Athabasca University as soon as possible. If you live in Calgaryor Edmonton, you can call the Learning Centre in your city and use theautomated telephone attendant to connectwith CourseMaterials (theextension is 6366). If you livewithin Canada or theUnited States, but outsideof Edmonton or Calgary, you can call the automated attendant by dialing1.800.788.9041. If you live outside of Canada or theUnited States, or if youdo notwish to use the automated system, you can call 780.675.6366. You canwrite to CourseMaterials, TimByrne Centre, 4001Hwy 2 South, Athabasca,AB T9S 1A4 or send electronicmail to

[email protected]

Commercial Materials

Brown, T. L., LeMay,H. E., Bursten, B. E., &Murphy, C. J. (contributingauthor). (2006).Chemistry: The Central Science,Volume 2 (custom editionfor Athabasca University). Saddle River, NJ: Pearson PrenticeHall.

Hill, J. C. &Wilson, R. (2006) Student’s Guide and Student SolutionsManual,Volume 2 (custom edition for Athabasca University). Saddle River, NJ:Pearson PrenticeHall.

StudentMediaPak: Chemistry the Central Science, 10th ed., Brown / LeMay /Bursten (2006).Upper Saddle River, NJ: Pearson PrenticeHall.

Athabasca University Materials

Chemistry 218: Chemical Principles II—StudentManual.Athabasca, AB:Athabasca University, 2007.

Chemistry 218: Chemical Principles II—Study Guide.Athabasca, AB: AthabascaUniversity, 2007.

Forms: The forms youwill need to submit assignments or inform theUniversity of a change in your status as a student are included in your coursepackage. You can also access forms online through your “myAU” portal (seethe section of thismanual titled “ThemyAUPortal”).


Other Materials

The items listed below are not supplied; you should purchase thembeforeyou begin towork on the course. Youwill need

an electronic calculator capable of handling logarithms and exponentials.

Remember: Take your calculatorwith youwhenever youwrite anexamination or attend a laboratory session.

other stationery, including paper for assignments, pens, pencils,a ruler, etc.

Course Website

Please visit theChemistry 218 coursewebsite, through yourmyAUportal.This site contains:

information about the course professor.

additional learning resources.

relevant links for the course.

Note:A student can pass the coursewithout visiting the coursewebsite.

Laboratories

Youmust complete on-site laboratorywork to obtain credit in this course.Information about the scheduled laboratory sessions is available through theCentre for Sciencewebsite.

Note that your laboratorywork accounts for 20% of your overall coursemark. Youmust satisfactorily complete andwrite up a specifiedminimumnumber of experiments in order to obtain credit for this course (see thesection of thismanual titled “Assessment”).

Note:We strongly recommend that you complete Units 14-17 beforeattempting any laboratorywork.


The Course Tutor

Athabasca University provides each student in each coursewith a tutorwhose responsibility is to help the student complete the course successfully.A letter containing your tutor’s name, address, telephone number, andtutoring hourswasmailed to you shortly before your official start date. Ifyou have not yet received your tutor letter, please contact LearningServices—Tutorial at Athabasca University as soon as possible. You can usethe automated attendant (see the “CourseMaterials” section of thismanualfor instructions, the extension is 6196); you can call 780.675.6196; or you cansend electronicmail to

[email protected]

Note: If you have chosen to receive communications fromAthabascaUniversity in electronic form, please check yourmyAUportal for your tutorletter.

Your tutor has excellent academic qualifications, and is committed tohelping students learning at a distance. He or she is available to answeryour questions about course content or how to approach a problem or anassignment, and can direct you to the right person or department to help youwith other problems thatmay be hindering your progress in your course orprogram. In addition, your tutorwill be responsible formarking yourassignments. In general, you should call your tutor first with any queriesaboutAthabasca University.

The tutor letterwill help you become acquaintedwith your tutor andwillprovide information about your tutor’s schedule. If you have not yet receiveda call fromyour tutor, do not hesitate tomake the first call yourself. If you livein Canada or theUnited States, youmay call your tutor, toll free, during hisor her tutoring hours, using the information provided in the tutor letter. Ifyou live outside of Canada or theUnited States, please refer to the tutor letterand the currentAthabasca University Calendar for information about callingyour tutor. Youmay find it useful to schedule a regular study periodwhenyour tutor is available so that you can call him or herwhen questions arise. Ifyou are unable to take advantage of the regular tutoring hours, contact yourtutor or the course professor to determinewhether alternative arrangementscan bemade.

We suggest that you call your tutor as soon as you receive the coursematerials, and then get into the habit of phoning regularly, when youcomplete a unit orwhen you run into any special problem.We have foundthat studentswhomaintain regular contactwith their tutors aremost likelyto be successful in completing their courses, so do keep in touch.

When youmail an assignment to your tutor, be sure to attach a tutor-markedexercise form, and to keep a copy, at least a rough draft, in case the originalgoes astray in themail. Note thatwe can only give credit forwork that isactually received; this is whywe strongly advise that you keep a rough copyof all of thework that you submit to your tutor formarking.


If youwish to submit your assignments electronically, contact your tutor todiscuss appropriate formats. An electronic version of the tutor-markedexercise form is available online through your “myAU” portal, or under “T”on the general index page

http://www.athabascau.ca/search/index.php?value=&type=index

Allow several working days, in addition tomailing time eachway, beforeyou expect to receive the graded assignment.

When you receive the graded assignment, review your tutor’s commentscarefully. Your tutorwill be pleased to provide additional feedback on yourassignments over the telephone. Be sure tomention any questions you haveabout the assignment or the grade.

Keep your tutor’s letter of introductionwith your coursematerials, and usethe space provided below to record information about your tutor.

Tutor’s name:

Address:

Telephone number:

Electronicmail address:

Tutoring hours:

The Course Professor

The course professor is themember of Athabasca University’s academic staffwho is in charge of a given course. The professorworks directlywith tutorson both academic and administrativematters. If you have difficulties youcannot resolvewith your tutor’s help, youmaywish to speakwith theprofessor directly. You should also address any questions about creditrecords or centrallymarked examinations to the course professor. Theprofessor can also provide general information about programplanningand curriculumdevelopment. The course professorwelcomes students’comments on the course.


Services to Students

Athabasca University offers awide range of services to its students. TheAthabasca University InformationCentre (1.800.788.9041) can help you findthe answer tomost administrative questions. The Centre is staffed on regularbusiness days from 7:00 a.m. to 5:30 p.m.Mountain Time.

Advisors are available to assist students in planning their programs andselecting appropriate courses. Counsellors assist students in improving theirstudy skills and clarifying their educational goals. Youmay reach an advisoror counsellor in several ways: by dialling 1.800.788.9041 and asking to speakwith an advisor or counsellor; by visitingAthabasca University’s CentralOffice inAthabasca, or the Learning Centre in Edmonton or Calgary; or bydirecting your query to

http://www.askau.ca

Studentswho are looking for information about student awards and adviceabout obtaining financial assistance are asked to contact theOffice of theRegistrar. Youmay do so by dialling 1.800.788.9041 and asking for theOfficeof the Registrar, or by inquiring through

http://www.askau.ca

Note: Studentsmaywrite examinations at theAthabasca University CentralOffice inAthabasca, at one of the Learning Centres, or at the other locationslisted online at

http://www.athabascau.ca/registrar/invignet.php

At the Learning Centres, students can also ordermaterials from the Library,and take care of various administrativematters, such as course registrationand arrangements for extensions. Other services include advice on programplanning and course selection, on developing a successful approach tostudying at a distance, on improving study habits and skills, and on careerand educational goal setting.

Indigenous Services at Athabasca University

If you are a student of Indigenous ancestry (Aboriginal, FirstNations, Indian,Inuit, Native,Métis) or a non-Indigenous studentwho is interested inidentifying culturally appropriate services designed for Aboriginal studentsor counselling that is sensitive to the challenges Aboriginal students face,please contact the Centre forWorld Indigenous Knowledge andResearch,by telephone at 1.800.788.9041, extension 2064, or by electronicmail at

[email protected]


Library Services

TheAthabasca University Library collection containsmore than 140,000books,many periodical titles, and a range of audio-visual resources. TheLibrary subscribes to over 100 online databases, providing full text access toselected articles frommore than 20,000 journals.

Athabasca University Library’s collection primarily supports AthabascaUniversity courses and programs.Materials found in the print and electroniccollections are available for use by our students, faculty, and staff forreference and research purposes. Requests for librarymaterials or servicescan bemade, by email, phone, fax, ormail, 24 hours a day (contactinformation is provided below). Responses tomost requests are handledwithin 24 hours, or by the next business day. Borrowedmaterials arenormallymailed to the student’s home address, alongwith a return-mailcard.

Core Services to Students

Athabasca University students registered in a coursemay

borrow librarymaterials.

search the Library’s online catalogue (AUCAT).

access resources through the Library’s website.

receive library instruction and research assistance.

request interlibrary loan (ILL) services for journal articles and bookchapters.

Digital Resources

Access to online journal databases, theDigital Reference Centre (DRC),and theDigital Reading Room (DRR) is available fromAthabasca UniversityLibrary’smainWeb page

http://library.athabascau.ca

Tips on searching the journal databases and helpwith researching, writing,and citing (referencing) can be found in theHelpCentre

http://library.athabascau.ca/help.php

Supplementary Materials

University courses often require that students investigatematerial beyondthe contents of the coursematerials package. SomeAthabasca University


courseStudyGuides list “SupplementaryMaterials,” including books, journalarticles, or audio-visualmaterials, which studentsmay find useful whencompleting assignments and course projects. The supplementarymaterialsreferenced in your coursematerials package are usually available from theAthabasca University Library or your local library. Contact theAthabascaUniversity Library to requestmaterials.

How the Library Gateway Works

The Librarywebsite contains the Library’s online catalogue (AUCAT), and itis also the gateway to other online information. Thewebsite provides links tojournal databases and other subscribed online resources, aswell as toselected, publicly accessible Internet sites. Subscribed resources are availabletoAthabasca University students, faculty, and staff. Youwill be required toenter your first and last names as your username, and your student IDnumber as your password.

The Librarywebsite also provides access to selected library catalogues fromCanadian public and academic libraries.

Interlibrary Loans

An interlibrary loan (ILL) involves one library borrowingmaterials fromanother on behalf of a library user. Athabasca University Librarywill requestphotocopies of journal articles and book chapters through Interlibrary Loans,if you provide the Library staff with a complete bibliographic citation(author, title of article, name of journal, volume and issue number, year ofpublication, and page numbers) for the requested item. You are not requiredto return these items to us. Allow sufficient time for thematerial to be orderedand received.More information on the Interlibrary Loan process is availableon the Librarywebsite at

http://aupac.lib.athabascau.ca/screens/ill.html

Contacts

Athabasca University Library1University DriveAthabasca, AB Canada T9S 3A3

Librarywebsite: http://library.athabascau.caEmail: [email protected]

Phone: 1.800.788.9041 (ext. 6254) Canada/US780.675.6254Other403.263.6465 (ext. 6254) in Calgary780.421.8700 (ext. 6254) in Edmonton

Fax: 780.675.6477


Supplementary Materials

Youwill find all the information you need tomaster the objectives in thetextbook and associatedmaterials. However, if youwant additionalinformation or a different perspective on a topic, or if youwant to readmoreabout a subject that interests you, ask your tutor if he or she can suggestsuitable books, articles, or audio visual aids pertaining to that particulartopic. TheAthabasca University library has, orwill attempt to obtain, copiesof all thematerials that your tutormight recommend, and thesematerials canbe sent to you on request.

Study Strategies

Chemistry 218 is a three-credit course andmust be completedwithinsixmonths of your official start date. Thismay seem like a long time, butprocrastination can rapidly put you in a difficult position.We suggest youstart right away and that you establish a study schedule. Your tutor canhelp you.

How fast you proceed through the first fewunits will depend on yourbackground in general chemistry. If your background isweak, youmayhave to put in extra time, and thismay affect your chances of completingthe coursewithin the normal six-month contract period. If you find that youreally have troublewithUnits 14 and 15, you should discuss the situationwith your tutor and considerwithdrawing from the course or taking someaction to improve your understanding of chemistry andmathematics.

At a traditional university, this coursewould normally be spread over onesemester and take about 12-13weeks to complete. If youwish to attain thisrate, follow the 13-week study schedule shown in the “CourseOutline andStudy Schedules” section of this StudentManual. If youwish to proceed atsomewhat slower pace, refer to the 18- and 26-week scheduleswhen youplan your own personal study schedule. Remember that regular study habitscan be amajor contributing factor to ultimate success in this course. Shouldunforeseen circumstances put you in a positionwhere you find that youcannot complete the coursewithin sixmonths, check theAthabasca UniversityCalendar for current regulations about extensions. [Youmaywish to checkthese regulations now, to ensure that you apply in a timelymanner.]


Assessment

The assessment of students in this course is based on examinations,tutor-marked assignments, and laboratorywork. Details are given in thetable below. To obtain credit forChemistry 218, youmust complete all of thecoursework, and achieve

an overall (composite)mark of at least 50%.

at least 50% on each of the two examinations.

Component Percentageof total mark

Midterm Examination(2 hours)

CoveringUnits 14-19

20%

Final Examination(3 hours)

CoveringUnits 14-25

40%

Tutor-markedAssignments

Following Units 16, 19,21, and 25

20%

Laboratory Work 20%

Both examinations are supervised and “closed-book.”However, youwillbe suppliedwith a periodic table and a list of appropriate data (physicalconstants, etc., but not formulas).

Remember:Youmust be sure to have your own electronic calculatorwithyouwhen youwrite an examination. You should also take along a pencil, incase you are required to draw a graph in any of the questions.

The samplemidterm and final examinations given in this StudentManualunder “Sample Examinations” are an excellent study resource.

Themidterm examination covers only thematerial inUnits 14-19, while thefinal examination encompasses Units 14-25.

If you are not satisfiedwith themark you obtain on your first attempt atan examination, youmay re-write that examination. The supplementalexaminationwill be similar in format to the first one, and the higher of thetwomarkswill be usedwhen your overall coursemark is determined. Youmustwrite a supplemental if you obtain less than 50% on an examination.Note that there is a fee for supplemental examination services.

The following hintsmay help you towrite examinations successfully.

1. Write an examination onlywhen you and your tutor feel that you areadequately prepared, andwhen you have successfully completed therelevant tutormarked assignments.

2. Remember that each examination is based on the list of objectivesprovided in each unit of the Study Guide.


3. Many of the questionswill be similar in format to those given in thetutor-marked assignments and in the sample examinations in thismanual.

4. For short-answer questions, do the ones that you find easiest first. Thisprocedure has two benefits. First, you canmore quickly accumulateenoughmarks to pass the examination. Second, you gain confidence totackle the harder questions.

5. For numerical, long-answer problems, showyourwork! Partmarkswillbe given for correctmethods, even if your answer is incorrect.

6. The answers to numerical problems should be given to the correctnumber of significant figures, andwhere appropriate, with the correctunits.Marksmay be deducted if answers are given to an incorrectnumber of significant figures or in thewrong (or no) units.

Please see the section of thismanual titled “Applying for andWritingExaminations” for further information.


Tutor-marked Assignments

Each of the tutor-marked assignments below isworth five per cent of yourfinal course grade. The assignments consist of two parts: a series of questionstaken from the textbook chapters, and sets of laboratory exercises taken fromtheVirtual ChemLab (VCL) included in theMediaPak that forms a part of yourcoursematerials. Note that for VCL exercises, you are asked to complete thetear-outworksheet for the designated exercise.

After you complete each assignment, submit it to your tutor for grading.Remember to attach a tutor-marked exercise form, from the course package,and to keep a copy (at least a rough draft) for your own files.

Tutor-marked Assignment 1 (Units 14-16)

Problems VCL Worksheets

Unit 14 / Chapter 14 14.30, 14.40, 14.48,14.66, 14.89, 14.90

—

Unit 15 / Chapter 15 15.22, 15.30, 15.38,15.56, 15.76

—

Unit 16 / Chapter 16 16.38, 16.44, 16.56,16.62, 16.78, 16.80,16.94, 16.133

VCL 16-1



Unit 17 / Chapter 17 17.14, 17.16, 17.26,17.42, 17.60, 17.66,17.80, 17.112

VCL 17-5

Unit 19 / Chapter 19 19.22, 19.40, 19.48,19.60, 19.80, 19.87,19.112, 19.113

VCL 19-1, VCL 19-2


Tutor-marked Assignment 3 (Units 20 and 21)


Unit 20 / Chapter 20 20.14, 20.20, 20.24,20.34, 20.46, 20.52,20.64, 20.66, 20.80,20.90, 20.125

VCL 20-1

Unit 21 / Chapter 21 21.16, 21.24, 21.28,21.36, 21.40, 21.48,21.80

—



Unit 22 / Chapter 22 22.34, 22.44, 22.68,22.76

—

Unit 23 / Chapter 23 23.14, 23.56, 23.77,23.83

—

Unit 24 / Chapter 24 24.12, 24.14, 24.24,24.26, 24.28

—

Unit 25 / Chapter 25 25.22, 25.26, 25.54 —


Applying for and Writing Examinations

Before youwrite the final examination for this course, you should havesubmitted all of your required course assignments and received feedbackfromyour tutor.

Although you do not need permission to apply for an examination, youare advised to consult your tutor about your readiness towrite, and aboutexaminationwriting strategies. Your tutor can also provide informationabout the examination format, and about study strategies.

To request an examination follow the steps below. Remember that requestsfor examinations from students inNorthAmericamust be received by theOffice of the Registrar aminimumof 15 business days before the intendedwriting date. Students elsewheremust allow additional time for shipmentof examinationmaterials.

1. Review the “Examinations andGrades” section of the currentAthabascaUniversity Calendar.

2. Arrange for a time towrite your examinationwith one of AthabascaUniversity’s Examination Centres orwith an invigilator. Fora list, see thewebsite

http://www.athabascau.ca/registrar/invignet.php

If youwould like to use an invigilatorwho has not been approved by theOffice of the Registrar, youmay propose their approval by filling in theappropriate details on the online Examination Request Form. Keep inmind that invigilatorsmay charge a fee, forwhich youwill beresponsible.

3. Complete and submit the online Examination Request Form. If you donot have access to the Internet, fill out the Examination Request Formfromyour coursematerials package and submit it by fax (780.675.6174);or in person or by postalmail to Examination Services, Office of theRegistrar, at Athabasca University’s central office.

Note: Tominimize the time required to process your application, be surethat you provide all of the information requested on the form, and thatyouwrite legibly.

4. Confirm that your invigilator has received the examination packagebefore you arrive towrite your examination. Take picture identificationand your student numberwith youwhen you go to the examination site.

The examination results and your final gradewill be sent to youapproximately four to sixweeks after youwrite the examination. Theexamination paper and your booklets or answer sheetswill not be returnedto you.


Appeals to examination or assignment grades should be discussed first withyour tutor or instructor. For the correct procedure, see “Student Code ofConduct and Right toAppeal Regulations” in the currentAthabascaUniversity Calendar.

Plagiarism and Academic Honesty

Students enrolled in anAthabasca University course such asChemistry 218are considered to be responsible scholars, and are therefore expected toadhere rigorously to the principles of intellectual honesty. Plagiarism is aform of intellectual dishonesty inwhich another’s work is presented as one’sown.As is the casewith any formof academicmisconduct, plagiarismwill beseverely penalized. Depending on the circumstances, penaltiesmay involverejection of the submittedwork; expulsion from the examination, the courseor the program; or legal action.

Students sometimes commit plagiarism inadvertently. To avoid doing so,make certain that you acknowledge all your sources both primary andsecondary in a full and consistentmanner. All direct quotes (quotations fromthe original work) and indirect quotes (paraphrases of ideas presented in theoriginal work)must be acknowledged. There are three conventional ways ofacknowledging your sources: in-text citations, footnotes or endnotes.Weprefer that you use endnotes.Whenever you use someone else’s work, placea subscript number at the end of that sentence or paragraph. The numbersrefer to a list of notes (or references) at the end of yourwriting assignment.This list must provide the author’s name, the title of thework, the name ofthe publisher and the place of publication, the page onwhich the citedmaterial appears, and the date of publication.

Note that all of the assignments you submit forChemistry 218must beoriginal work completed especially for this course. The use of assignmentsyou have completed for other courses, or assignments completed by otherstudents, are both considered cheating, andwill be penalized as such.

Transferring Credit

If youwish to transfer credit to another institution, contact theOffice of theRegistrar at Athabasca University. Remember, though, that transfer of creditis determined by the receiving institution. If you plan to transferChemistry 218to another institution, we suggest you get an agreement, inwriting, from thatinstitution.


Transcripts

A studentmay request an official transcript by completing a paper“Transcript Request” form, bywriting to theOffice of the Registrar, byappearing at theOffice of the Registrar in person, or by using the secureonline request form. For instructions onmaking an online request,please see

http://www.athabascau.ca/registrar/transcripts_FAQ.php

Only the studentwhose transcript is being issuedmaymake the request,and a paper requestmust bear the student’s signature.

No partial transcripts are issued. The student’s entire record is shown oneach transcript.

Most institutions and agencies require that official transcripts be sent directlyfromAthabasca University. Please allow aminimumof tenworking days forthe receipt of a transcript. Consult the current edition of theAthabascaUniversity Calendar for further information about transcripts.

Applying for Extensions

If you are unable to complete this coursewithin the six-month coursecontract period, youmay apply for and purchase up to three, two-monthextensions. Note that extension request formsmust be received by theOfficeof the Registrar aminimumof onemonth before the end of your coursecontract. Requests for second and third extensionsmust be received by theOffice of the Registrar aminimumof onemonth before the expiry of theprevious extension. Consult the onlineAthabasca University Calendar formoreinformation about obtaining extensions.


Course Outline and Study Schedules

The table below gives a brief course outline and suggests the amount of timestudents should spend on each unit for 13-, 18- and 26-week schedules.

Note: Studentswho are receiving financial assistancemay face special timeconstraints. Please check your course registration for any restrictions on thelength of registration, and be prepared to adjust your schedule.

Unit number and title 13-weekschedule

18-weekschedule

26-weekschedule

14 Chemical Kinetics Week 1 Weeks 1-2 Weeks 1-3

15 ChemicalEquilibrium

Week 2 Weeks 2-3 Weeks 3-4

16 Acid-BaseEquilibria (TMA 1)

Week 3* Weeks 4-5 Weeks 5-6

17 Additional Aspectsof AqueousEquilibria

Week 4 Weeks 6-7 Weeks 7-8

18 Chemistry of theEnvironment

Week 4 Week 7* Week 9

19 ChemicalThermodynamics(TMA 2)

Week 5 Weeks 8-9 Weeks 10-12*

14-19 Review for andwrite MidtermExamination

Week 6 Week 10 Week 13

20 Electrochemistry Week 7 Weeks 11-12 Weeks 13-15

21 Nuclear Chemistry(TMA 3)

Week 8 Week 13 Weeks 16-18

22 Chemistry of theNonmetals


23 Metals andMetallurgy

Week 10** Week 15** Weeks 21-22

24 Chemistry ofCoordinationCompounds

Week 11 Week 16 Weeks22-23**

25 The Chemistry ofLife: Organic andBiologicalChemistry(TMA 4)


14-25 Review for andwrite FinalExamination

Week 13 Week 18 Week 26

* RequestMidtermExamination** Request Final Examination


Sample Examinations

On the following pages youwill find sample examinations thatwill helpyou to prepare for yourmidterm and final examinations.We have includedsuch questions in thismanual so that studentsmay obtain a better idea of thelength of a normal Athabasca University chemistry examination. Shortanswers for the questions are given at the end of the sample examinations.

During an actual examination youwould be providedwith a periodic tableand a data sheet of physical constants. Note that the data sheet contains noformulas.

Examination answer keys appear inAppendixA of thismanual.

Sample Midterm Examination

Themidterm examination is two (2) hours long. In the actual examinationyouwould not be allowed consult your books or notes; however, youwouldbe able to use a calculator.We strongly recommend that you sit thisexamination as if youwerewriting it in an invigilated setting. Youwill get amuch better idea of your degree of preparedness for the actual examination.

Part A: Short-answer Questions (1 mark each)

1. In the chemical reactionA+ B 2C, the rate of decrease in [A]wasmeasured to be 2.0Ms−1.Whatwas the rate of increase in [C]?

2. A given reactionwas found to follow first order kinetics, with a rateconstant k= 8.3 10−2 s−1.What is the half-life of this reaction?

3. If the reaction between atomic chlorinewith ozone,Cl+O3ClO+O2, is an elementary reaction, what is the rate lawfor this reaction?


4. In a study of the effects of temperature on the rate of reactionCl+O3ClO+O2, the following equation for the rate constantwasfound:

k= (1.75× 1032M−1s−1)e−260T

What is the activation energy for the reaction Cl+O3ClO+O2, inunits kJ/mol?

5. For the equilibrium reactionN2(g)+ 3H2(g) 2NH3(g), write theexpression forKc.

6. For the equilibrium reactionN2(g)+ 3H2(g) 2NH3(g), write theexpression forKp in terms ofKc.

7. For the reversible reaction 2A+ B 2C, the equilibrium constantKc= 1.85. If amixture of A, B, andC has concentrations [A]= 0.40M,[B]= 0.40M, and [C]= 0.30M,will the reactionmixture shift to the left(to reactants) or the right (to the product)?

8. A 1.0 L vessel was initially filledwith pureNOBr(g) to a pressure of4.0 atm. The final partial pressure of NOBrwas 2.5 atm after thefollowing equilibriumwas established: 2NOBr(g) 2NO(g)+ Br2(g).What is the value ofKp?


9. What is the pH of 0.25M formic acid (Ka= 1.8 10−4)?

10. What is the percent ionization of 0.25M formic acid?

11. The pKa of the amino acid glycine is 2.35.What is theKb of the conjugatebase of glycine?

12. What is the pH of a 1.0Mglycine solution?

13. What is the pH range of a buffered solution composed of equalmolarconcentrations of acetic acid and acetate? (Ka= 1.8 10−5)

14. What is the pH of a solution composed of 0.40M acetic acid and 0.20Msodium acetate?


15. What is the solubility of Ag3PO4 in purewater? (Ksp= 2.6 10−18)

16. What is the solubility of PbI2 (Ksp= 7.9 10−9) in a solution that contains0.20Mpotassium iodide?

17. The equilibrium constant,Keq, for a given reaction under standardconditions is 8.0 106.What is the value of G298 for this reaction?

18. For the chemical reaction Cl2O(g)+ 3/2O2(g) 2ClO2(g), H=126.4 kJ/mol and S=−74.9 J/molK.What is the value of G at350 K?

19. For a particular reaction, H= 5.5kJ/mol and S=−25 J/molK. Inwhat temperature range is this reaction spontaneous?

20. A chemical reaction has G= 20.0 kJ/mol and S= 50.0 J/molK.What is the value of H at 298K?


Part B: Long Answer (5 marks each)

21. At 298 K, the kinetics of a chemical reactionwere studied and thefollowing initial rate datawere obtained.

A+ BC

Experimentnumber

[A] (M) [B] (M) Initial Rate(M/s)

1 0.020 0.010 3.2 10−4

2 0.030 0.010 7.2 10−4

3 0.020 0.020 6.4 10−4

What is the rate law for this reaction andwhat is the value of the rateconstant at 298 K?


22. For the chemical system shown below, it was found that [N2]= [O2]=0.70mol/L and [NO]= 0.22mol/L, at equilibrium. Suppose thatenoughN2was added to increase its concentration temporarily to 1.00mol/L.When the system reaches equilibrium,whatwill be the newequilibrium concentrations of N2, O2, andNO?

N2(g)+O2(g) 2NO(g)


23. A bufferwasmade that consisted of 500mL of 0.90MNH3 and 500mLof0.90MNH4

+. TheKa ofNH4+ is 5.6 10−10.

a. Calculate the pH of the buffer.

b. Calculate the resulting pH if 0.02mol of HCl is added to the originalbuffer.

c. Calculate the resulting pH if 0.02mol of NaOH is added to theoriginal buffer.


d. Calculate the resulting pH if 0.06mol of HCl is added to the originalbuffer.


24. Explain the differences inmolar entropies of the following elements inthe states given.

Substance S (J/molK)

C(diamond) 2.43

C(graphite) 5.74

He(g) 126.2

Ar(g) 154.8

Pb(s) 64.8

Hg(l) 75.9


Sample Final Examination

The final examination is three (3) hours long. In the actual examination youwould not be allowed consult your books or notes; however, youwould beable to use a calculator.We strongly recommend that you sit this examinationas if youwerewriting it in an invigilated setting. Youwill get amuch betteridea of your degree of preparedness for the actual examination.


1. For the following electrochemical equation, write the half-reaction thatoccurs at the anode:

Zn(s)+Cu2+(aq)Zn2+(aq)+Cu(s)

2. Complete and balance the following electrochemical equation, underacidic conditions:

Cr2O72−

(aq)+Cl−(aq)Cr3+(aq)+Cl2(g)

3. In the following reaction, which chemical species is the oxidizing agentandwhich is the reducing agent?

3CN−(aq)+H2O(l)+ 2MnO4−(aq) 3CNO−(aq)+ 2MnO2(s)+ 2OH−(aq)


4. What is the free energy change,G, associatedwith the followingelectrochemical reaction? Report your answer in units kJ/mol.

Zn(s)+Cu2+(aq)Zn2+(aq)+Cu(s)

5. Calculate the cell potential, E, for a voltaic cell composed of onecompartment containing a Pb(s) electrode immersed in 1.0MPb2+(aq),and a second compartment containing a Pt(s) electrode immersed inwater that is saturatedwithH2(g).

6. What is the cathode half-reaction that occurs in a hydrogen fuel cell,under acidic conditions?

7. Howmany kilograms of aluminumare produced in 24.0 hours by theelectrolysis ofmoltenAlCl3, if the current is 100.0 A?

8. What isotope decays, by beta emission, to give13154Xe?


9. A given radioactive isotope has a decay constant of 1.6 10−10 yr−1.What is the half-life of this isotope?

10. List twoways to detect radioactivity.

11. Calculate the binding energy of the nucleus of 56Fe, given that theisotopicmass is 55.92068 amu, the protonmass= 1.00728 amu, and theneutronmass= 1.00866 amu. Report your answer in joules to twosignificant figures.

12. Write a balanced chemical equation, including states, for the reactionbetween hydrogen gas and calciummetal.

13. Write a balanced chemical equation, including states, for the reactionbetween PBr3(l) andwater.


14. Write a balanced chemical equation, including states, for the reactionbetween zincmetal and aqueous hydrochloric acid.

15. Write the balanced chemical equation, including states, for the roastingof zinc sulfide.

16. Write down the half-reaction that occurs at the cathode in theHallprocess.

17. Write balanced chemical equations for the oxidation of Fe2+ in aqueoussolution, in the presence of oxygen.

18. What is the oxidation number of the cobalt atom in the complex[Co(NH3)5Cl]Cl2?

19. What is the systematic name of the complex [Co(NH3)5Cl]Cl2?


20. What kind of isomerism(s) does the following compound exhibit:

cis−[Co(en)2Cl2]+ ?

21. What is the IUPACname for the followingmolecule?

22. What are the three components of a nucleotide?

23. The disappearance of ozone follows the equation 2O3(g) 3O2(g). Overa certain time interval, the average rate of disappearancewas found to be9.0 10−3 atm/s.What is the rate of appearance of O2 during the sametime interval?

24. A first order reaction has a rate constant k= 3.2 10−3 s−1.What is t1/2?


25. For the equilibrium reactionN2O4(g) 2NO2(g), write the expressionforKp.

26. For the equilibrium reactionN2O4(g) 2NO2(g),Kp= 1.09. If PNO2=0.20 atm and PN2O4= 0.040 atm,will the reaction proceed to the left orthe right?

27. What is the expected pH of an aqueous solution containing0.50MCH3COOH (Ka= 1.8 10−5)?

28. What is the expected pH of an aqueous solution containing0.50MCH3COOH (Ka= 1.8 10−5) and 0.50MNaCH3COO?

29. For a given reactionA+ BC, G=−56.0 kJ/mol.What is theequilibrium constant for this reaction at 298 K?


30. Calculate the value of Ssys for the following reaction, using theinformation in the table below:

2Fe(s)+ 3/2O2(g)+ 3H2O(l) 2Fe(OH)3(s)

Substance S (J/mol K)

Fe(s) 27

Fe(OH)3 107

O2(g) 205

H2O(l) 70



31. a. What relative concentrations of Cu2+(aq) must be used to construct aconcentration cell based on twoCu electrodes andCu2+(aq)solutions, with a cell potential of 0.055 V? (assume T= 298 K)

b. Sketch a figure of the concentration cell from (a) that clearly labelsthe cathode, anode, relative solution concentrations, and direction ofelectron flow.


32. Explain how cathodic protection can prevent the corrosion of ironexposed to air andwater. Include any relevant chemical equations inyour answer.


33. Carbon-14 has a half life of 5715 years.

a. Write a balanced nuclear reaction for the beta decay of 14C.

b. Howmany yearswill it take for the radioactivity of a 14C sample todecrease to 10% of the original radioactivity?


34. a. Describe the structure and properties of carbon dioxide.

b. Write a balanced equation for a laboratorymethod of producingcarbon dioxide.

c. Write a balanced chemical equation for the reaction between carbondioxide andwater.


35. Draw all possible isomers of the Co(III) compoundCo(NH3)4Cl3.Writethe names of each isomer and identify the type(s) of isomerism.


36. A solution containing an unknown concentration of benzoic acid(Ka= 6.5 10−5) is titrated using a standardized solution of sodiumhydroxide.

a. Sketch the titration curve, labeling the equivalence andhalf-equivalence points.

b. What is the pH at the half-equivalence point?

c. What is the pH at the equivalence point, if the approximateconcentration of benzoate ionswas 0.050M?


Appendix A: Answer Keys

Sample Midterm Examination

Part A: Short Answer Questions (1 mark each)

1. Rate= 4.0Ms−1

2. t½= 8.3 s

3. Rate= k[Cl][O3]

4. Ea= 2.16 kJ/mol

5. Kc=[NH3]2

[N2][H2]3

6. Kp=Kc(RT)−2

7. Shift to the right (to the product)

8. Kp= 0.27

9. pH= 2.17

10. % Ionization= 2.7%

11. Kb= 2.2 10−12

12. pH= 1.18

13. The pH range is between 3.74 and 5.74

14. pH= 4.44

15. Solubility= 1.8 10−5M

16. Solubility= 2.0 10−7M

17. G298=−39 kJ/mol

18. G= 152.6 kJ/mol

19. This reaction is not spontaneous at any temperature.

20. H= 34.9 kJ/mol



21. The rate law can be determined by examining how the initial ratechangeswith changes in reactant concentrations. Between experiments 1and 2, [B] is held constantwhile [A] is increased from 0.020M to 0.030M,a factor of 1.5; the initial rate changes from 3.2 10−4 to 7.2 10−4, afactor of 2.25. Noting that 2.25= 1.52, the reaction is second orderwithrespect toA.

Between experiments 1 and 3, [A] is held constantwhile [B] is increasedfrom 0.010M to 0.020M, a factor of 2; the initial rate changes from3.2 10−4 to 6.4 10−4, a factor of 2. Thus, the reaction is first orderwithrespect to B.

The rate law for this reaction is:

Rate= k[A]2[B]

The rate constant can be found by substituting concentrations and initialrate into the rate law and solving for k.

Rate= k[A]2[B]

3.2× 10−4Ms−1= k(0.020M)2(0.010M)

k= 80M−2s−1

22. First, the value ofKcmust be calculated using the equilibriumconcentrations of N2, O2, andNO:

Kc=[NO]2

[N2][O2]=

(0.22mol∕L)2(0.70mol∕L)(0.70mol∕L)= 0.10

To solve this equilibriumproblem, the following equilibrium table isused:

N2 O2 NO

Initial Concentration (mol/L) 1.00 0.70 0.22

Concentration Change (mol/L) −x −x +2xEquilibrium Concentration(mol/L)

1.00− x 0.70− x 0.22+ 2x

Substituting the equilibrium concentrations into the equilibriumexpression gives:

Kc=[NO]2

[N2][O2]=

(0.22+ 2x)2(1.00− x)(0.70− x)= 0.10

Rearranging gives the following quadratic equation:

3.90x2+ 1.05x− 0.0216= 0

This quadratic equation can be solved using the quadratic formula,which gives two possible answers: x= 0.02mol/L or x=−0.29mol/L.


The only plausible answer is x= 0.02mol/L. The equilibriumconcentrations are:

[N2]= 1.00− x= 0.98mol∕L

[O2]= 0.70− x= 0.68mol∕L

[NO]= 0.22+ 2x= 0.26mol∕L

23. a. As the concentrations of the conjugate acid-base pair are identical,the pH is equal to the pKa, which is 9.25.

b. The number ofmoles of NH3 present is 0.90M 0.500 L= 0.45mol.Likewise, the number ofmoles of NH4

+ present is 0.90M 0.500 L= 0.45mol.

When 0.02mol ofHCl is added, it reactswithNH3 to produceNH4+,

giving the following concentrations:

[NH3]= 0.45mol− 0.02mol1.00L = 0.43M

[NH+4 ]=

0.45mol+ 0.02mol1.00L = 0.47M

The resulting pH can be calculated using theHenderson-Hasselbachequation:

pH= pKa+ log[base][acid]

= 9.25+ log 0.43M0.47M= 9.21

c. Calculating in amanner similar to (b), the new concentrations ofNH3 andNH4

+ are:

[NH3]= 0.45mol+ 0.02mol1.00L = 0.47M

[NH+4 ]=

0.45mol− 0.02mol1.00L = 0.43M

The resulting pH is:


= 9.25+ log 0.47M0.43M= 9.29


d. Calculating in amanner similar to (b) and (c), the new concentrationsof NH3 andNH4

+ are:

[NH3]= 0.45mol− 0.06mol1.00L = 0.39M

[NH+4 ]=

0.45mol+ 0.06mol1.00L = 0.51M

The resulting pH is:


= 9.25+ log 0.39M0.51M

= 9.13

24. Themolar entropies of these substances increase in the following order:

C(diamond) <C(graphite) < Pb(s) <Hg(l) <He(g) <Ar(g)

This is in order of solid < liquid < gas, which is expected formolarentropies.

The carbon solids have the lowestmolar entropies of the solids becausecarbon has a lowmolecularweight and because diamond and graphiteare highly ordered, crystalline solids. The diamondmolecular structureismore highly ordered than graphite.

Of the two gases, heliumhas a lowermolar entropy because it has alower atomicmass than argon.


Sample Final Examination


1. Zn(s)Zn2+(aq)+ 2e−

2. 14H+(aq)+Cr2O72−

(aq)+ 6Cl−(aq) 2Cr3+(aq)+ 7H2O(l)+ 3Cl2(g)

3. The oxidizing agent isMnO4−(aq), and the reducing agent is CN−(aq).

4. G=−212 kJ/mol

5. E=+0.13 V

6. O2(g)+ 4H++ 4e− 2H2O(l)

7. 0.805 kg of aluminum

8.13153 I

9. t½= 4.3 109 years

10. Any two of photographic film, Geiger counters, or scintillation counters.

11. Binding energy= 7.9 10−11 J

12. Ca(s)+H2(g)CaH2(s)

13. PBr3(l)+ 3H2O(l)H3PO3(aq)+ 3HBr(aq)

14. Zn(s)+ 2HCl(aq)ZnCl2(aq)+H2(g)

15. 2ZnS(s)+ 3O2(g) 2ZnO(s)+ 2SO2(g)

16. Al3+(l)+ 3e−Al(l)

17. 4Fe2+(aq)+O2(g)+ 4H+(aq) 4Fe3+(aq)+ 2H2O(l)

18. +3

19. Pentaamminechlorocobalt(III) Chloride

20. Optical isomerism

21. Cyclohexane

22. Phosphoric acid, 5−carbon sugar, nitrogen containing organic base

23. Rate= 1.4 10−2 atm/s

24. t½= 2.7 102 s


25. Kp=(PNO2)

2

PN2O426. The reactionwill proceed to the right

27. pH= 2.52

28. pH= 4.74

29. K= 6.55 109

30. Ssys=−358 J/mol K



31. a. E= EO− RTnF lnQ

E= EO− 0.0592n logQ

0.055V= 0V− 0.05922 logQ

Q= 0.014=[Cu2+]anode[Cu2+]cathode

The relative concentrationsmust be 0.014:1

b.

32. When ironmetal is oxidized to Fe2O3xH2O, the first step is the oxidationof Fe(s) to Fe2+(aq):

Fe(s) Fe2+(aq)+ 2e−

Because Fe(s) is being oxidized, it is the anode.

In cathodic protection, ironmetal ismade to be the cathode by bringing itin contactwith ametal that has amore positive oxidation potential (e.g.,zinc). Thismetal will then become the anode (it is oxidized), and ironmetal will become the cathode atwhich the reduction half reactionoccurs:

O2(aq)+ 4H+(aq)+ 4e− 2H2O(l)

33. a.146 C→

147 N+

0---1 e


b. k= 0.693t1∕2= 0.6935715y= 1.21× 10

−4 y−1

ln[14C]t[14C]0

= ---kt

ln0.101.00 = ---(1.21× 10−4 y−1)tt= 1.90× 104 y

34. a. CO2 has a linear structure, with the following Lewis structure:

It is non-toxic. As a gas, it is colourless and odorless. The solid form,known as dry ice, exists at−78C.

b. NaHCO3(s)+H+(aq)Na+(aq)+CO2(g)+H2O(l)

c. CO2(g)+H2O(l)H2CO3(aq)

35. Geometric isomerism


36. a.

b. pKa= --- logKa= --- log(6.5× 10−5)= 4.19

c. Kb=KwKa= 1.0× 10

−14

6.5× 10−5 = 1.5× 10−10

Kb= 1.5× 10−10=[HA][OH−][A ---] =

(x)(x)0.050− x≅

x20.050

x= 5.55× 10−5M= [OH−]

pOH= 4.26

pH= 9.74

chemistry 218 - athabascau.ca20 electrochemistry week 7 weeks 11-12 weeks 13-15 21 nuclear chemistry...

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