chemistry 330 environmental chemistry - athabascau.ca · 2 environmentalchemistry the myau portal...

Chemistry 330Environmental Chemistry

Student Manual

AthabascaUniversitya

Course Team

Course Coordinator: Lawton ShawRevisions: Lawton Shaw (2006)Editor:Gilda SandersVisual Design: Ian GrivoisWebDesign:KonradMichalskiVisual Presentation:Athabasca University Digital Media Technology Unit

This course is a revision of an earlier version ofChemistry 330 prepared bythe following course team:

Author andCourse Coordinator:Dietmar KennepohlEditor: Erna DomineyVisual Design: Ian GrivoisWebDesign:KonradMichalskiVisual Presentation:Athabasca University Typesetting Unit

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 anymaterials in this publication is strictly in accordwith theconsents obtained andAthabascaUniversity does not authorize or licenseany further reproduction or usewithout the consent of the copyright holder.

EAthabascaUniversity 2002, 2006All rights reservedPrinted inCanada

CMID537669

Contents

Introduction 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ThemyAU Portal 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Your Student ID Number 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Athabasca University Calendar 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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

Course Contract 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Course Design 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Your Course Tutor 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Course Professor 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Services to Students 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Library Services 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Course Outline and Study Schedule 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Studying for this Course 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Assessment of Students’Work 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Applying for andWriting Examinations 18. . . . . . . . . . . . . . . . . . . . . . . . . .

Writing Essays 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Intellectual Indebtedness and Plagiarism 27. . . . . . . . . . . . . . . . . . . . . . . . .

Transcripts 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Credit Transferability 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sample Examinations 29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SampleMid-term Examination 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Answers to SampleMid-term Examination 33. . . . . . . . . . . . . . . . . . . . . . .

Sample Final Examination 36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Answers to Sample Final Examination 38. . . . . . . . . . . . . . . . . . . . . . . . . . .

Chemistry 330 / Student Manual 1

Introduction

Welcome toChemistry 330: Environmental Chemistry, a three-credit,intermediate-level course dealing with the chemistry of air, soils, and water,human impacts on them, and the implications of these impacts forenvironmental and human health.

Issues concerning our health and environment have become increasinglyimportant in recent years. Ozone depletion, the “greenhouse effect,” heavymetal poisoning and acid rain are only a few controversial issues that havecome to the public’s attention through the media. Often, in discussions ofthese phenomena, “facts” are (intentionally or unintentionally) misrepresented,exaggerated, or taken out of context. It becomes difficult to weigh theimportance of much of this information when one is constantly bombardedbymedia sensationalism.

It has become increasingly important for young scientists not only to beaware of environmental and health issues, but also to be well informed aboutthem.Chemistry 330: Environmental Chemistrywill provide a broadoverview of many important environmental issues. It will also give studentsthe most reliable and recent scientific information available, so that they maydraw independent and informed conclusions about these issues.

Environmental chemistry is a multidisciplinary subject with inputs from suchfields as meteorology, engineering, geology, ethics, politics, physics, medicine,toxicology, and chemistry. Students enrolled in this course must have completedAthabasca University’sChemistry 217 and 218 (Chemical Principles I and II)or equivalent first-year chemistry courses at the university level.

This Student Manual contains essential information about the design of thecourse, the course materials, and the procedures that you should follow toobtain the maximum benefit from your studies. Please read it carefully, andkeep it in a safe place.

Note: These course materials have been designed for students who are takingthe individualized-study version of this course. Students in a grouped-studyenvironment should follow the course outline, study schedule, and learningactivities provided by their instructor.

2 Environmental Chemistry

The myAU Portal

MyAU is a personalized portal to the University where youmay quicklyaccess information that is relevant to you, including on-line components ofyour courses. ThroughmyAU, you can view personal information, such aslibrary accounts and assignment marks and course grades, and take care ofadministrative matters, such as booking examinations, submittingassignments, applying for extensions, registering for courses, and so on.Athabasca University will also communicate directly with you throughmyAU. Check theMessage Centre on your myAU home page for bothgeneral information and for mail addressed specifically to you.

To login at

http://my.athabascau.ca/

enter your student ID number and password where requested. If you arehaving browser difficulties or you need help, refer to myAUHelp at

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

Your Student ID Number

In contacts with your tutor, on examinations, or in any correspondence or othercontact with the University, you are asked to provide your student ID number.Record this number in the space below. Having your student ID number helpsUniversity staff to process your requests, grades, and administrative mattersmore quickly.

Student ID number:

Note: The personal information and records collected andmaintained by theUniversity 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 theAlberta Freedom of Information and Protection of Privacy Act.

The Athabasca University Calendar

Because Athabasca University’s policies, practices, and procedures changeover time, some of the information in this Student Manualmay lose itscurrency between course revisions. Students are therefore advised to refer tothe current Athabasca University Calendar on important issues concerningUniversity policies, procedures, and practices. In the event of anydiscrepancy between the printed version of theCalendar and the officialWeb-basedCalendar, theWeb-based version will be binding.


Course Materials

The package you received should include each of the items listed below. Ifanything is missing from your package, please contact the CourseMaterialsdivision of Athabasca University as soon as possible. If you live in Calgary orEdmonton, you can call the Learning Centre in your city and use the automatedtelephone attendant to connect with CourseMaterials (the extension is 6366).If you live within Canada or the United States, but outside of Edmonton orCalgary, you can call the automated attendant by dialing 1.800.788.9041. Ifyou live outside of Canada or the United States, or if you do not wish to usethe automated system, you can call 780.675.6366. You can send electronicmail to

[email protected]

or write to CourseMaterials, TimByrne Centre, 4001 Hwy 2 South,Athabasca, AB T9S 1A4.

Textbooks

Baird, Colin, andMichael Cann.Environmental Chemistry, 3rd ed. NewYork:W. H. Freeman and Company, 2005.

Baird, Colin. Student SolutionsManual for Environmental Chemistry, 3rd ed.NewYork:W. H. Freeman and Company, 2005.

Note: Errata for the Student SolutionsManual are provided at theWebsite for Environmental Chemistry, 3rd ed.:

http://bcs.whfreeman.com/envchem3e/

Athabasca University Materials

Chemistry 330: Environmental Chemistry—Student Manual. Athabasca, AB:Athabasca University, 2006.

Chemistry 330: Environmental Chemistry—Study Guide.Athabasca, AB:Athabasca University, 2006.

Chemistry 330: Environmental Chemistry—Assignment Manual.Athabasca,AB: Athabasca University, 2006.

Forms: The course package contains the forms you need to submit assignments,request an examination, or notify the University of a change in your status asa student.

You should spend a fewminutes familiarizing yourself with these materials.


The items listed below are not supplied; you should purchase them beforeyou begin to work on the course.

1. an electronic calculator, preferably a “scientific” calculator, capableof handling logarithms and exponentials.Note:Remember to take yourcalculator with you whenever you write an examination or attend alaboratory session.

2. stationery, including paper for assignments, pens, pencils, a ruler,according to your needs.

Course Contract

Chemistry 330: Environmental Chemistry is a three-credit course, andis equivalent to a one-semester course at a conventional university. It isoffered in individualized-study delivery mode, and is normally open tostudents throughout the year. Students can determine their own timelinesfor completing it, up to a maximum of six months. Nonetheless, they areencouraged to follow the study schedule in this Student Manual. Studentswho do so will have no difficulty in completing the course requirementswithin the six-month contract period. However, students who findthemselves running short of timemay purchase an extension to theircourse contract. The Athabasca University Calendar contains informationon obtaining an extension to a course contract. Youmay wish to review thisinformation to ensure that you apply in a timely manner.


Course Design

Athabasca University course materials are designed for self-instructionand study.What you should learn and how you should learn it are describedin the Study Guide. The Study Guide begins with a general chemistry reviewunit. Each of Units 1 to 11 in the Study Guide corresponds to one chapter inyour textbook, Environmental Chemistry. Each Study Guide unit containsan overview of the relevant textbook chapter, sections corresponding to thesubdivisions of the chapter, and hints on how to review the unit.

Let us look at exactly what you can expect to find under each heading in theStudy Guide.

1. Every unit in the Study Guide begins with an Overview. It contains abrief discussion that outlines the the textbook authors’ overall approachto the material convered in the chapter.

2. For each section in the textbook, you will find that the Study Guide contains

a. a list of objectives. These objectives may be one of the most valuablefeatures of the Study Guide, because they tell you explicitly what youmust understand and be able to do for each section of each unit.Questions on the examinations and tutor-marked assignments arebased only on the section objectives. However, you should be awarethat many questions will require you to demonstrate mastery of anumber of related objectives, and you should not place too narrow aninterpretation on each objective.

b. a list of key terms introduced in the section.

c. some study notes. These notes may include hints on how to study thematerial effectively, additional information, and details of any errorsthat occur in the textbook.

d. suggested exercises selected from those given at the end of eachchapter of the textbook. The purpose of doing these exercises is toimprove your understanding of the material you have just studiedand to develop your problem-solving skills. Refer to your notes andto the textbook when you attempt these exercises. You will find theanswers in the Student SolutionsManual for EnvironmentalChemistry, 3rd ed., by Colin Baird. Domake a concerted effort toanswer each question independently, but do not spend a large amountof time on any one exercise: if you are unable to make any progressafter a fewminutes of concentrated work, use the answers to help.Many of the answers are laid out in stepwise fashion, and often, afterchecking the first step, you will be able to proceed on your own.


3. Each unit ends with the “Review Procedure,” a short list of steps that youshould take when reviewing the unit and completing any relatedassignments.

There are four tutor-marked assignments inChemistry 330. These assignmentscontribute to the overall mark that you will obtain for the course (see thesection of this manual titled “Assessment of Students’Work”).

The textbook, Environmental Chemistry, 3rd ed., by Colin Baird andMichaelCann, contains most of the information you will need to pass this course. It isa standard textbook used in several universities and colleges throughoutNorth America. It was chosen because it offers clear explanations andinteresting discussions of the material covered in this course.


Your Course Tutor

Athabasca University provides each student in each course with a tutorwhose responsibility is to help the student complete the course successfully.A letter containing your tutor’s name, address, telephone number, electronicmail address, and tutoring hours was mailed to you shortly before yourofficial start date. If you have not yet received your tutor letter, please contactLearning Services—Tutorial at Athabasca University as soon as possible.You can use the automated attendant (see the “CourseMaterials” section ofthis manual for instructions, the extension is 6196); you can call780.675.6196; or you can send electronic mail to

[email protected]

Your tutor has excellent academic qualifications, and is committed to helpingstudents learning at a distance. He or she is available to answer your questionsabout course content or how to approach a problem or an assignment, and candirect you to the right person or department to help you with other problemsthat may be hindering your progress in your course or program. In addition,your tutor will be responsible for marking your assignments. In general, youshould call your tutor first with any queries about Athabasca University.

The tutor letter will help you become acquainted with your tutor and willprovide information about your tutor’s schedule. If you have not yet receiveda call from your tutor, do not hesitate to make the first call yourself. If youlive in Canada or the United States, you can call your tutor, toll free, duringhis or her tutoring hours, using the information provided in the tutor letter. Ifyou live outside of Canada or the United 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 period whenyour tutor is available so that you can call him or her when questions arise. Ifyou are unable to take advantage of the regular tutoring hours, contact yourtutor or the course professor to determine whether alternative arrangementscan bemade.

We suggest that you call your tutor as soon as you receive the course materials,and then get into the habit of phoning regularly, when you complete a unit orwhen you run into any special problem.We have found that students whomaintain regular contact with their tutors are most likely to be successful incompleting 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 the mail. Allow several working days, in addition to mailingtime each way, before you expect to receive the graded assignment. If youwish to submit your assignments electronically, contact your tutor to discuss


appropriate formats. An electronic version of the tutor-marked exercise formis available on-line under “T” on the general index page

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

Your tutor will be pleased to provide additional feedback on yourassignments over the telephone. Be sure to mention any questions you haveabout the assignment or the grade.

Keep your tutor’s letter of introduction with your course materials, and usethe space below to record information about your tutor.

Tutor’s name:

Address:

Telephone number:

Electronic mail address:

Tutoring hours:

The Course Professor

The course professor is the member of Athabasca University’s academic staffin charge of a given course. The course professor works directly with tutorson both academic and administrative matters. If you have difficulties youcannot resolve with your tutor, you may wish to speak with the professordirectly. You should also address any questions about final grade reports orcentrally marked examinations to the professor. He or she can also providegeneral information about program planning and curriculum development.The course professor welcomes students’ comments on the course.


Services to Students

Athabasca University offers a wide range of services to its students. Advisorsare available to assist students in planning their programs and selectingappropriate courses. Counsellors assist students in improving their studyskills and clarifying their educational goals. You can reach an advisor orcounsellor in several ways: by dialling 1.800.788.9041 and asking to speakwith an advisor or counsellor; by visiting Athabasca University’s CentralOffice in Athabasca, or the Learning Centre in Edmonton or Calgary; or byreferring to the FAQ section of the Ask AUWeb site:

http://www.askau.ca

Students who are looking for information about student awards and adviceabout obtaining financial assistance are asked to contact the Office of theRegistrar. You can do so by dialling 1.800.788.9041 and asking for the Officeof the Registrar, or by directing your query through

http://www.askau.ca

Note: Students may write examinations at the Athabasca University CentralOffice in Athabasca, at one of the Learning Centres, or at the other locationslisted on-line at

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

Indigenous Services at Athabasca University

If you are a student of Indigenous ancestry (Aboriginal, First Nations, Indian,Inuit, Native, Métis) or a non-Indigenous student who is interested inidentifying culturally appropriate services designed for Aboriginal studentsor counseling that is sensitive to the challenges Aboriginal students face,please contact the Centre forWorld Indigenous Knowledge and Research, bytelephone at 1.800.788.9041, extension 2064, or by electronic mail at

[email protected]


Library Services

The Athabasca University Library collection contains more 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 for referenceand research purposes. Requests for library materials or services can bemade,by e-mail, phone, fax, or mail, 24 hours a day (contact information is providedbelow). Responses to most requests are handled within 24 hours, or by the nextbusiness day. Borrowedmaterials are normally mailed to the student’s homeaddress, along with a return-mail card.

Core Services to Students

Athabasca University students registered in a course may

borrow library materials.

search the Library’s online catalogue (AUCAT).

access resources through the Library’sWeb site.

receive library instruction and research assistance.

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

Digital Resources

Access to online journal databases, the Digital Reference Centre (DRC),and the Digital Reading Room (DRR) is available fromAthabasca UniversityLibrary’s mainWeb page

http://library.athabascau.ca

Tips on searching the journal databases and help with researching, writing,and citing (referencing) can be found in the Help Centre

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

Supplementary Materials

University courses often require that students investigate material beyond thecontents of the course materials package. SomeAthabasca University courseStudy Guides list “SupplementaryMaterials,” including books, journal


articles, or audio-visual materials, which students may find useful whencompleting assignments and course projects. The supplementary materialsreferenced in your course materials package are usually available from theAthabasca University Library or your local library. Contact the AthabascaUniversity Library to request materials.

How the Library Gateway Works

The LibraryWeb site contains the Library’s online catalogue (AUCAT), andit is also the gateway to other online information. TheWeb site provides linksto journal databases and other subscribed online resources, as well as toselected, publicly accessible Internet sites. Subscribed resources are availableto Athabasca University students, faculty, and staff. You will be required toenter your first and last names as your username, and your student ID numberas your password.

The LibraryWeb site 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 Library will 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 the material to beordered and received.More information on the Interlibrary Loan process isavailable on the LibraryWeb site at

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

Contacts

Athabasca University Library1 University DriveAthabasca, AB Canada T9S 3A3

Library web site: http://library.athabascau.caEmail: [email protected]

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

Fax: 780.675.6477


Course Outline and Study Schedule

The table below gives a brief course outline and suggests the amount of timethat students should spend on each unit to complete the course in a 13-, 18-or 26-week period. Students with a good background in chemistry andmathematics should select one of the shorter schedules. The 26-weekschedule is primarily for students whose skills in chemistry andmathematicsneed work.

Note: Students who are receiving financial assistance or those in a grouped-study version of this course should check their course registration for specialrestrictions on the length of registration, and should be prepared to adjusttheir schedules.

Unit TextbookChapter

Title 13-weekschedule

18-weekschedule

26-weekschedule

1 1 Stratospheric Chemistry: TheOzone Layer

1 1–2 1–3

2 2 Ground-Level Air Pollution—Indoors and Ourdoors

2 3–4 4–6

3 3 The Detailed Chemistry of theAtmosphere (TMA1)

3 5 7

4 4 The Greenhouse Effect andGlobalWarming

4 6-7 8-9

5 7 Toxic Organic Chemicals—Pesticides (TMA2)

5 8 10-11

1–5 1–4, 7 Review andmid-term exam 6 9 126 8 Nonpesticide Toxic Organic

Compounds of EnvironmentalConcern

7 10 13–14

7 9 The Chemistry of NaturalWaters

8 11-12 15–16

8 10 The Pollution and PurificationofWater (TMA3)

9 13 17–18

9 11 Toxic HeavyMetals 10 14 19–2010 12 Hazardous andMunicipal

Wastes, and the Contaminationof Soils and Sediments

11 15 21–22

11 13 Radioactivity, Radon, andNuclear Energy (TMA4)

12 16 23–24

Complete Term Paper 11–12 17 251–11 1–4, 7-13 Review and final exam 13 18 26


The following table is designed to assist you in planning a personalized studyschedule (with the help of your tutor). We suggest you begin by filling in thefirst few units and keep track of how long each unit is taking you. After youhave done the first few units, you (and your tutor) should be able to come upwith a realistic schedule for the rest of the course.

Unit Planned completiondate

Actual completiondate

Time required(hours)

Action necessarywhen completed

Receivecourse

Contact tutor.

Unit 1

Unit 2

Unit 3 Complete TMA1.

Unit 4 Request mid-termexam.

Unit 5 Complete TMA2.Request mid-termexam.Write mid-term exam.

Unit 6

Unit 7 Choose term papertopic.Order material fromlibrary.

Unit 8 Complete TMA3.

Unit 9 Request final exam

Unit 10

Unit 11 Complete TMA4.Write term paper.Write final exam


Studying for this Course

Chemistry 330 is a three-credit course, and must be completed within thesix months of your course contract period. This may seem like a long time,but procrastination can rapidly put you in a difficult position.We suggest thatyou start right away and establish a study schedule. Your tutor can help you.How quickly you proceed through the first few units will depend on yourbackground in first-year university chemistry. If your background is weak,youmay have to put in extra time, and this may affect your chances ofcompleting the course within the normal six-month contract period. If youfind that you really have trouble with Units 1 and 2, discuss the situation withyour tutor and consider withdrawing from the course, or taking some actionto improve your basic understanding of chemistry andmathematics.

At a traditional university, this course would normally take 12–13 weeks tocomplete. If you wish to work at this rate, follow the 13-week study scheduleshown in the first table in the “Course Outline and Study Schedules” sectionof this Student Manual. If you wish to proceed at a somewhat slower rate,refer to the 18- and 26-week schedules when you plan your study schedule.Remember that regular study habits can be amajor contributing factor toultimate success in this course. Should unforeseen circumstances put you ina position where you find that you cannot complete the course within thesix-month contract period, youmay request an extension. Check theAthabasca University Calendar for the current regulations governingextensions; there are time limits to which youmust adhere.

We suggest that you start in on Unit 1 now. As you work through it, make anote of any questions you have on content, study procedures, and so on. Then,before you go on to the next unit, contact your tutor to clear up these questions.

As you study each unit inChemistry 330, follow the procedure outlined below.

1. Read the overview at the beginning of every unit. At this stage, somestudents find it beneficial to preview the unit by reading through thewhole chapter in the textbook.

2. Study each section in the unit by

a. reading the list of objectives at the beginning of the section.

b. reading the list of key terms.

c. reading the corresponding section of the textbook, and using theobjectives and key terms as a guide whenmaking notes.

d. reading the study notes (if any). These notes may contain study hintsor additional information, and will also identify any errors that occurin the relevant section of the textbook.


e. completing the assigned exercises, and checking your answers in theStudent SolutionsManual for Environmental Chemistry, 3rd ed.Note that your problem-solving ability will largely determine theoverall grade you receive in this course. The exercises represent theminimum number of exercises that you should try.

3. Review the unit by making sure that

a. you understand all of the objectives and can do what they require.

b. you can define and use the key terms.

4. Do the “tutor-marked assignment” (if there is one), and send it to yourtutor for grading.

Warning:With distance education, assignments may occasionally get lost inthe mail. As Athabasca University can only give credit for work that hasactually been received, we strongly advise that you keep a copy of all thework that you submit to your tutor for marking.


Assessment of Students’ Work

The assessment for this course is based upon examinations, tutor-markedassignments (TMAs) and a term paper. Details can be found in the tablebelow. To obtain credit forChemistry 330, you must

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

2. achieve at least 45% on each of the two examinations.

3. obtain an average of at least 60% on the tutor-marked assignments.

4. achieve at least 60% on the term paper.

Component Material covered Percentageof total mark

Mid-term examination (2 hours) Units 1–5 20%Final examination (3 hours) Units 1–11 40%Tutor-Marked Assignments (TMAs) Units 1-3, 4-5, 6-8, 9-11 20%Term paper Essay topic 20%

Both examinations are supervised and “closed book.” However, you will besupplied with a periodic table and a list of appropriate data (constants, etc.).Youmust be sure to have your own electronic calculator with you when youwrite an examination. You should also take along a pencil, in case you arerequired to draw a graph in any of the questions. There are nomultiple-choice questions on the examinations.

Note that, as the mid-term examination tests Units 1-5, the emphasis(60–70%) in the final examination is on Units 6–11.

If you are not satisfied with the mark that you obtain on an examination, itmay be possible for you to rewrite that examination.We strongly advise thatyou consult the most recent edition of theAthabasca University Calendar toobtain details of any recent or pending changes to the regulations governingsupplemental examinations. Any supplemental examination will be similarin format to the first one, and the higher of the twomarks will be used whenyour overall course mark is determined. There is a fee for supplementalexaminations.

The following hints may help you to write examinations successfully.

1. Write the examination only when you and your tutor feel that you areadequately prepared, and when you have successfully completed therelevant tutor-marked assignments.


2. Remember that the examinations are based on the objectives outlined inthe Study Guide. Many of the questions will be similar in format to thosegiven in the tutor-marked assignments and in the examples given in thesection of this manual titled “Sample Examinations.”

3. For short answer questions, do the ones that you find easiest first. Thisprocedure has two benefits. First, you can more quickly accumulateenoughmarks to pass the examination. Second, you gain confidenceto tackle the harder questions.

4. For numerical problems, show your work! Part marks will be given forcorrect methods, even if your answer is incorrect.

5. The answers to numerical problems should be given to the correctnumber of significant figures, and where appropriate, with the correctunits. Marks may be deducted if answers are given to an incorrectnumber of significant figures or in the wrong (or no) units.

After you have written an examination, please be patient while you wait forthe result. Examinations rarely reach our central offices in less than five days,and a ten-day lapse fromwhen the examination is written to its arrival inAthabasca is not unusual. Chemistry examinations are normally markedwithin twenty-four hours of receipt, and your tutor is informed of the markbefore your next tutor night.Writing an examination one day and calling thecourse professor a few days later does not expedite the marking process.

For security reasons, examinations cannot be returned to students, nor can theprofessor enter into detailed discussions of specific examination questions.After each of your examinations is corrected, somewritten comments will besent to you. Your tutor will also receive a copy of these comments, and youshould discuss the issues raised with your tutor at the first suitable occasion.Only then, if you are still dissatisfied with your mark, should you contact thecourse professor. If you still cannot obtain a satisfactory explanation of howyour grade was determined, please refer to the currentAthabasca UniversityCalendar for information about the formal appeals procedure.


Applying for and Writing Examinations

Before you write the final examination for this course, youmust havesubmitted all of your required course assignments and received feedbackfrom your tutor.

Although you do not require permission to apply for the examination, you areadvised to consult your tutor about your readiness to write it, and aboutexamination writing strategies. Your tutor can also provide information aboutthe examination format, and about study strategies.

To request an examination follow the steps below. Students in North Americamust request examinations a minimum of 15 business days before theintended writing date. Students elsewhere must allow additional time forshipment of examination materials.

1. Review the “Evaluation” section of the currentAthabasca UniversityCalendar.

2. Arrange for a time to write your examination with one of AthabascaUniversity’s Examination Centres or with an invigilator. For a list ofExamination Centres, see theWeb site

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

If you would like to use an invigilator who has not been approved by theOffice of the Registrar, you may propose their approval by filling in theappropriate details on the online Examination Request Form. Keep inmind that invigilators may charge a fee, for which you will beresponsible.

3. Complete and submit the online Examination Request Form. If you donot have access to the Internet, fill out the Examination Request Formfrom your course materials package and submit it by fax (780.675.6174);or in person or by postal mail 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 thatyou write legibly.

4. Confirm that your invigilator has received the examination packagebefore you arrive to write your examination. Take picture identificationand your student number with you when you go to the examination site.

The examination results and your final grade will be sent to you approximatelyfour to six weeks after you write the examination. The examination paper andyour booklets or answer sheets will not be returned to you.


To receive credit for the course, youmust submit all the course assignmentsand complete them to the satisfaction of your tutor. Youmust also obtain agrade of 50 per cent or better on each course examination, and a coursecomposite grade of at least 50 per cent.

Supplemental Examinations and Appeals

Students who are dissatisfied with their grade on any examination, or whoobtain less than the required passing grademay write a supplementalexamination. The passing grade for supplemental examinations is50 per cent, and only one supplemental is permitted per examination. Thehigher of the two grades received will be recorded as the official grade. Thereis a fee for supplemental services.

Appeals

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


Writing Essays

An essay written for a university course serves twomain purposes. The firstand most obvious is pedagogical: researching a topic and writing about it isan excellent way of learning. The second function served is evaluation: anessay enables the instructor to assess the student’s ability to explain thesubject in a lucid and cogent fashion, to integrate the different types ofmaterial covered, to analyse events or themes, and to place them in acomprehensible order.

Although developing good essay writing skills is important, it need not be anarduous task. A few basic principles that students must keep in mind arelisted below.

1. An essay should have an evident structure. Open your essay with anintroduction that states the problem you wish to explore or the questionyou plan to answer. Examine the most important facets of the topic, anddiscuss the issues that have been (or ought to be) the subject of scholarlydebate. Develop your own argument, and present your evidence in thebody of the essay.When your argument is complete and well presented,end your work with a conclusion that summarizes the problem orquestion and states your judgement or answer.

2. An essay should contain a well-developed argument and the evidence forthis intellectual position. It should contain a point of view, perhaps morethan one, expressed logically and supported by evidence that has beenappropriately documented; and it should lead to a conclusion thatappears natural and persuasive in the light of the evidence presented. Anessay must also contain a discussion and analysis of the material that isbalanced and judicious, taking opposing arguments into account, andrecognizing where the available information is insufficient orinconclusive.

3. An essay must be based on adequate and appropriate reading andreflection, and must acknowledge intellectual indebtedness throughproper citations. A superior essay should also show evidence ofindividual thought: originality will be valued highly by the marker,provided, of course, that the case is properly argued and not merelyeccentric.

Your grade will reflect howwell you havemet these standards. In attemptingto achieve these goals, you will develop and practise several intellectualskills that will prove invaluable to you throughout your university career:


1. the ability to synthesize information from a variety of sources;

2. the ability to analyse the significance of primary source material;

3. the ability to make appropriate use of secondary source material(e.g., summarizing the research that has been done on a topic, placing itin context, and noting similarities to and differences from other writers’presentations);

4. the habit of documenting, carefully and honestly, the sources of yourinformation and ideas; and

5. the ability to develop a cogent, balanced and well-supported argument.

These skills are necessary for essay writing, and they are developed by essaywriting. One of the benefits of refining these skills is that they will serve you,not only in the classroom, but also in every other area of your life.

Structure

There is no single model that youmust follow to write a good essay.Thoughtful, creative and well-argued essays may be organized in variousways. However, if you need help with the mechanics of constructing essays,the following suggestions will help you to organize and to write yourassignments.

Introduction or Thesis Statement

Begin your essay by stating the problem, issue or topic that you are going toaddress in the paper, and outline the approach you are going to take in dealingwith it. This initial paragraph is sometimes called a ”thesis statement.” Athesis statement is a sentence or series of sentences that defines a subject anda particular position on or understanding of that subject. To construct a thesisstatement, you must have a general understanding of the topic and aconsiderable amount of detailed and specific knowledge of the material; andyoumust have thought through what you are going to say in the paper. Youmust have considered each argument that supports your view and eachargument that undermines it. Youmust also have analysed the mostreasonable means of presenting your argument. So, although you only needto provide a single statement, to produce that statement youmust (a) knowthe parameters of the question; (b) know the specific vocabulary thatdescribes the question; and (c) be familiar with the arguments that support,and those that undermine, your position on the question.

You should regard your initial thesis statement as tentative and preliminary innature. As you continue to analyse your material, your approach may well


shift. Keep the statement in mind, but be flexible. Do not reject informationor fail to include it because it disproves your statement. The statement youbegin with may change several times as you progress. Youmay find yourselfreorganizing the order of the material, shifting the discussion or changingyour position. Do not be alarmed by this process: it is an indicator that youare thinking and coming to grips with your material. Youmay find that youend up writing the final version of your introduction after you havecompleted the main body of your paper.

Organization

Most people find it useful to construct an outline of the main components ofthe paper, and then follow the outline when writing the text. The statementof organization is a short passage that follows your thesis statement andexplains how you will analyse the topic and present your arguments. It helpsyou clarify how you will prove and document your ideas, and it serves yourreader as a conceptual map of the structure of your paper.

An essay is composed of an introduction, a main body and a conclusion.Of course, the main body of the essay will be a lot longer than either theintroduction or the conclusion, and will normally contain several differenttopics and discussions. As you sketch an outline, the main body of the essaywill expand to accommodate these various sections. Consequently, youressay outline may at some point look like this:

I. Introduction

1. Interesting opening sentence (background, quotation, something tointerest and entice the reader)

2. Thesis statement

3. Statement of organization (the order of the points you will make tojustify your interpretation)

II. Main Body

1. Section 1

a. Statement of main idea or key argument

b. Supporting evidence

dates/statistics

illustration/example

sequence of events

c. Summary of the main point

d. Link to Section 2


2. Section 2

a. Main idea

b. Supporting discussion

c. Summary

d. Link to Section 3

3. Section 3 . . .

4. Section 4 . . .

etc.

III. Conclusion

1. Reiteration of the initial problem or question at issue

2. Summary of your analysis and key arguments (including all the maintopics covered)

3. Overall conclusion based on evidence presented

With a complete and thoughtful outline, the writing of the essay is simply amatter of fitting the research you have done into the pattern that you havemade. Just follow the outline, making sure that the progression of informationis logical and that your arguments are well supported by evidence andanalysis.

Editing

In writing a final draft, the quality of language and the logic of the argumentare the principal concerns: by the final draft, there should be no factual,grammatical or spelling errors. Producing the final draft is a matter ofrefining and editing your penultimate draft. There are two types of editing.The first, often called substantive editing, is for sense: read each sentence,making certain that it is complete (has a subject, a verb, and if necessary, anobject), and that the preceding and following sentences are linked andlogical. Examine each section of the essay for clarity and coherence. Youmight ask yourself the questions listed below.

1. Introduction: Is it interesting? Is the thesis statement clear? Does it definethe exact subject and express a point of view? Does the statement oforganization cover all the topics?

2. Main Body: Does each paragraph cover a different point? Is it relevant tothe thesis? Does it have a topic sentence? Are details present, and do theysupport the topic sentence, and in turn, the thesis? Does it provide properreferences? Does it contain a rich vocabulary?


3. Conclusion: Does it restate the thesis? Does it provide a summary of thematerial? Does it present a clear, valid conclusion?

The second type of editing is copy editing, and is effectively done line-by-line, from the end to the beginning of the document. As you copy edit, youcheck spelling, typing, footnote numbers, consistency of capitalization, etc.This step is a crucial one in the preparation of essays, because many small,annoying errors can be as damaging to the sense and impact of your essay as afew large, obvious ones. Good copy editing is a difficult task for an author. Adifferent pair of eyes, coming fresh to the text, will normally pick uptypographical errors that you havemissed simply because you are toofamiliar with your ownwork to notice them. Therefore, if you can findsomeone else to help you read your final draft, you will almost certainly endup with a cleaner, more error-free, manuscript. An alternative strategy is toput your final draft in a drawer for a couple of days before attempting to copyedit it yourself. Even if time pressure precludes this option and you havenobody available to help you, it is important that you do your best to copyedit your paper. Copy editing is the last stage of the essay writing process. Itwill be very evident to your reader if you have not taken the trouble to finishthe job properly.

References

When you write an academic essay, it is sometimes difficult to knowwhen toreference information. A general rule is that a well-known textbookmay beconsidered a baseline. Everyone has access to it, and so the information in itcan be considered common knowledge. In-text citations, footnotes orendnotes are necessary whenever you use material from another source.

It is important to document figures, dates, and specific events as well asideas. Of course, every fact and idea in the essay could be referenced, so youhave to make judgements about what it is necessary or reasonable and usefulto document. Knowing when to reference another source is a skill that youwill develop as you learn to refine your writing.

There are three occasions when references are necessary.

1. A reference must always accompany a quotation. The essay is a productof your thinking and should be written in your ownwords. Youmay,however, come across a passage in your reading that expresses perfectlyan idea that you think is necessary to include. Simply to copy anotherwriter’s text into your essay without acknowledging the source isplagiarism. In academic circles plagiarism is considered a grave offence,and can lead to serious consequences. Youmay, however, copy thepassage and acknowledge the source in a reference. If the quotation is


longer than four or five lines, it should be indented and single-spaced,and followed by a reference.

2. References are also used to acknowledge intellectual indebtedness in amore general manner. For example, youmay have summarized in oneparagraph the main ideas and arguments of a scholarly paper that you arelisting in your bibliography. Even if you have employed no directquotations, it is customary to have a reference at the end of the paragraphindicating the source of the information contained therein.

3. Similarly, if you are discussing (in your ownwords) several alternativeinterpretations of a topic or controversial issue you can (and should) usereferences to indicate to your reader the books and articles in which eachof these interpretations has been advanced. Often the way in which atopic or issue is conceptualized, and the terms that are employed todiscuss it, implicitly suggest an interpretation or perspective on thesubject. Different authors use the same or similar terminology, but theymean something different by those samewords.

In each of these cases, the material you have cited, the phrase or sentence,should be followed by a reference. Select one of the styles below foryour essay:

1. an in-text citation, which provides the name of the author, the date, andthe page number, if applicable, in parenthesis; for example (Thompson1990: 161).

2. a small superscripted Arabic number, presented at the end of thephrase or sentence, that directs the reader to a footnote or endnote;for example, “ . . . economic valorization of symbolic forms.”1

3. an asterisk, which directs the reader to an explanation at the bottom of thepage; for example, “. . . economic valorization of symbolic forms.”*

Whichever style of notation you choose, provide a full bibliographicreference.When using in-text citations, gather your information together in areference list at the end of the essay. For example, a reference to Thompson inthe essay (Thompson 1990: 161) would be included in the reference list:

Thompson, John B. Ideology andModern Culture. Stanford, CA: StanfordUniversity Press, 1990.

or, if you are using American Psychological Association (APA) style:

Thompson, John B. (1990). Ideology and modern culture. Stanford, CA:Stanford University Press.


4. When using either footnotes or endnotes, the number refers to thematerial that appears at the bottom of the page (footnotes) or on aseparate page at the end of your essay (endnotes). The first time you referto a book, you should provide full bibliographical reference:

1. John B. Thompson, Ideology andModern Culture, p. 161. Stanford, CA:Stanford University Press, 1990.

The second time the book appears, you can cite it as follows:

11. Thompson, Ideology, p. 162.

Note: Footnotes, endnotes or unnumbered notes may also be used to make anexplanation that would otherwise interrupt the flow of the argument, toexplain a foreign word or phrase, or to give additional biographicalinformation. However, if you find that you are using explanatory notes toooften, you should rethink your outline. Generally, if something is importantenough to be included in your essay at all, it should find an appropriate placein your main text. Explanatory notes should be the exception, not the rule,and you should always have a very good reason for resorting to them.

Bibliography

The last step in essay preparation is the bibliography, a separate listing of allthe works that you actually used in the process of writing your essay,including books you read but did not quote from, as well as books you quotedor cited. The list should be arranged alphabetically by the first author’ssurname and initials. The Study Guide contains suitable examples.

Note:When you prepare your bibliography, youmay underline the title of abook or use italics; do not do both.

Essay Presentation

For the convenience of your tutor, leave fairly wide margins. They facilitatethe insertion of corrections and comments, and make your essay easier to read(a decided psychological advantage). The ideal margins are approximately fourcentimetres at the left and two and one-half centimetres at the top, bottom andright-hand side.Whether you are typing or writing in longhand, pleasedouble-space your paper. Before submitting your essay, be sure to proof-readit carefully to catch any spelling mistakes, typing errors and the like. Do notwrite in pencil.

Last but by nomeans least, please keep a copy of your paper (at least therough draft), just in case the original should go astray in the mail.


Intellectual Indebtedness and Plagiarism

Students enrolled in any Athabasca University course are considered to beresponsible scholars, and are therefore expected to adhere rigorously to theprinciples of intellectual honesty. Plagiarism is a form of intellectualdishonesty in which another’s work is presented as one’s own, and, as willany form of academic misconduct, plagiarismwill be severely penalized.Depending on the circumstances, penalties may involve rejection of thesubmitted work; expulsion from the examination, the course or 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 consistent manner. All direct quotes (quotations,however short, from an original work) and indirect quotes (paraphrases of ideaspresented in an original work) must be acknowledged. There are threeconventional ways of acknowledging your sources: in-text citations,footnotes, or end-notes.We prefer that you use in-text citations, combinedwith a full bibliography presented at the end of the essay. The in-text citationmust give the name of the author, the date of publication, and the page onwhich the cited material appears (Doe, 1997, p. 60). The bibliographic entrymust provide at least the author’s last name, first name or initial, the date ofpublication, the title of the work, the place of publication and the publisher.For further information, see the section of this manual titled “WritingEssays.”

Dutiful citation of quotes and paraphrased material does not mean you canwrite an essay assignment by stringing together a series of quotes. Youshould always try to summarize or describe someone else’s ideas in yourownwords. If you present your own ideas or opinions in a paper, providesubstantiated evidence or arguments for your position.

All assignments must be original work for this course. The use ofassignments from previous courses or from other students is considered aform of cheating and will be subject to discipline for academic misconduct.

For more information on this important matter, see theAthabasca UniversityCalendar.


Transcripts

A student can request an official transcript by completing a paper “TranscriptRequest” form, by writing to the Office of the Registrar, by appearing at theOffice of the Registrar in person, or by using the secure on-line request form.For instructions onmaking an on-line request, please see

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

Only the student whose transcript is being issued maymake the request, and apaper request must bear the student’s signature.

No partial transcripts are issued. The student’s entire record is shown on eachtranscript.

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

Credit Transferability

If you wish to transfer credit to another institution, contact the Office of theRegistrar at Athabasca University. Remember, however, that transfer of creditis determined by the receiving institution. If you plan to transferChemistry 330to another institution, we suggest you get an agreement, in writing, from thatinstitution.


Sample Examinations

On the following pages you will find sample examinations that will help youto prepare for your mid-term and final examinations.We have included suchquestions in this manual to give you a better idea of the length of a normalAthabasca University chemistry examination. Short answers are given formost of the questions, and can be found at the end of the sampleexaminations.


Sample Mid-term Examination

Themid-term examination is two hours long. As you write the examination,youmay not consult any books or notes. However, the use of a calculator orslide rule is permitted. You will also be provided with a periodic table and aset of standard physical constants (i.e., a data sheet).

Part A: Short-answer Questions

Each question in this section is worth 3 marks.[30marks]

1. Complete the following table.

Radiation Type Spectral Range(nm)

Primary Absorber of Sunlight

UV-A 320–400 NO2

280–320UV-C O2 and O3

2. Write the two-step noncatalytic photochemical reactions for thedestruction of stratospheric ozone. (Hint: Last half of the Chapmanmechanism.)

3. The rate constant for

OH+O3HO2+O2

can be expressed as:

k=1.9×10−12 e(−1000/T)

Calculate the activation energy.

4. Henry’s Law constant for oxygen is 1.3×10−3 M atm−1 at 25_C.Calculate the amount of dissolved oxygen in water at sea level.

5. List three commercial uses of asbestos.

6. Based on structure, circle the compounds below that you expect wouldabsorb infrared radiation.

Ar O3 Cl2

CO2 H2 CF4

7. The atmosphere contains 3.9×1015 tonnes of nitrogen gas. Annuallosses of nitrogen include thunderstorms (6.9×107 tonnes) and nitrogenfixation by bacteria (2.1×108 tonnes). Calculate the residence time ofnitrogen in the atmosphere.


8. For DDT, logKow = 6.What is the approximate bioconcentration factorfor DDT in fish?

9. Draw the general structure of a carbamate.

10. Hydroxyl radicals are key in the oxidation of hydrocarbons in thetroposphere. Compare the first step (i.e., OH attack) in the oxidation ofmethane and ethene (ethane?).

Part B: Long-answer Questions

The possible marks for each question are indicated in square brackets.

11. In an experiment, it is found that 0.00124mg of hexachlorobenzene(HCB) can be dissolved in exactly 200.0 mL of water.

a. What is the solubility of HCB in water, in units of ppm? [3 marks]

b. What is the solubility of HCB in water, in units of moles per litre?[3 marks]

12. Briefly explain why temperature decreases with altitude in thetroposphere, but increases with altitude in the stratosphere. [10marks]

13. The rate constant for the attack of methane by the hydroxyl radical isabout 3.6×10−15 cm3 molecule−1 s−1. Assume that[OH]=8.0×105molecule cm−3 and[CH4]=4.5×1013 molecule cm−3.a. Calculate the rate of atmospheric methane removal in

molecule cm−3 s−1. [6 marks]

b. If the total volume of the atmosphere is 4.3×1018 m3, howmanytonnes of CH4 is removed each year? [8 marks]

14. In your ownwords, briefly define five (5) of the following terms.[2 marks each]

fuel cellVOCphenoxy herbicidenitrificationhomonuclear diatomic moleculeenhanced greenhouse effectacid rainCFC

[10marks]


Answers to Sample Mid-term Examination

1. Complete the following table.

Radiation Type Spectral Range(nm)

Primary Absorber of Sunlight

UV-A 320–400 NO2

UV-B 280–320 O3

UV-C 200–280 O2 and O3

2. O3+h (<320 nm)→ O2+OO+O3 → 2O2

3. Arrhenius equation

k=Ae(−Ea/RT)=1.9×10−12e(−1000/T)

By inspection we notice that

Ea/RT=1000/TSolve for activation energy (Ea)

Ea=(1000)R=(1000)(8.134×10−3)=8.1 kJ

4. [X (aq)]=KH×P=(1.3×10−3 M atm−1)(0.21 atm)=2.7×10−3 M

5. Uses include insulation, fireproofing buildings, brake-pad lining, cementadditive, roofing and pipes, and fireproof clothing.

6. CO2, O3, and CF4 should be circled because they can absorb infraredradiation.

7. Tavg=C/R

= (3.9×1015 tonnes)/( 6.9×107+2.1×108 tonnes y−1)= 1.4×107 y

8. logKow = 6, soKow= 1,000,000. For fish,Kow serves as a reliableapproximation for BCF. Hence, BCF 1,000,000.


9. General structure of carbamate:

O

ONH

CH3

R

10. Hydrogen abstraction:

a. CH4+OH CH3+H2O

b. OHAddition:

c. H2C=CH2+OH H2C−CH2(OH)

11. a.solubility=

0.00124 mg0.2000 L

= 0.00620 mg∕L

= 0.00620 ppm

b. molar mass HCB= 284.76 g/mol

n=0.00124 mg284.76 g∕mol

= 4.35× 10−9mol

solubility=4.35× 10−9 mol

0.2000 L

= 2.8× 10−8 mol∕L

12. The temperature in the troposphere is controlled by absorbed infraredradiation emitting from the Earth’s surface. Increased distance from thesurface results in a lower temperature. However, in the stratosphere atemperature inversion occurs through increased occurrence of ozoneformation

O+O2+M O3+M (heat released)

which is in turn controlled by incoming sunlight (<241 nm). Togetherthese processes determine the temperature profile and therefore thedistinction between troposphere and stratosphere.


13. a. Rate=k[OH][CH4]

=(3.6×10−15 cm3 molecule−1 s−1)×( 8.0×105 molecule cm−3)×(4.5×1013 molecule cm−3)=1.30×105 molecule cm−3 s−1

b. First, 4.3×1018 m3=4.3×1024 cm3

also, one year has 365.25 days or 31557600 seconds.

Molecules CH4 removed in one year

=Rate of removal×Volume×Time=(1.30×105 molecule cm−3 s−1)( 4.3×1024 cm3)( 31557600 s)

=1.76×1037 moleculesMoles(CH4)=molecules/N

=(1.76×1037 molecule)/(6.022×1023 molecule mol−1)=2.93×1013 mol

Mass(CH4)=Moles(CH4)×MolecularWeight(CH4)

=(2.93×1013 mol)(16 gmol−1)=4.69×1014 g or 4.69×1011 kg or 4.69×108 tonnes

14. fuel cell: primary electrochemical cell in which reactants arecontinuously supplied from outside

VOC: volatile organic compound (e.g., butane)

phenoxy herbicide: a class of herbicides made by reacting a phenoxideanion with an alkyl halide (e.g., 2,4--D)

nitrification: reduced nitrogen is oxidized (e.g., NH3NO3−)

homonuclear diatomic molecule: two-atommolecule having the sameatoms (e.g., N2 or Cl2)

enhanced greenhouse effect: increased trapping of thermal infraredenergy by anthropogenic sources of gases

acid rain : any precipitation having a pH of less than 5

CFC: chlorofluorocarbon (e.g., CFC-11 which is CFCl3): CFCs are ofenvironmental interest because of their damaging effect on stratosphericozone.


Sample Final Examination

The final examination is three hours long. As you write the examination, youmay not consult any books or notes. However, the use of a calculator or sliderule is permitted. You will be given a periodic table and a set of standardphysical constants (i.e., a data sheet).

Part A: Short-answer questions

Each question in this section is worth 3 marks.[30marks]

1. Circle all species below that are considered common oxidizers inhazardous waste.

H2O2 CH3CH2CH3 CaSiO4

NH3 KMnO4 HClO4

2. Calculate the equilibrium concentration (in ppm) of Pb2+ in water sittingover excess PbSO4.

3. Explain the difference between point and nonpoint sources of pollution.Give an example of each.

4. What equivalent dose (in g) of 2,3,7,8-TCDD corresponds to thefollowing 10.0 g mixture of dioxins?

Dioxin Weight% TEQ

A 30 0.5B 45 0.01C 25 0.1

5. Write down the chemical equation that illustrates that water exposed tocarbon dioxide is acidic.

6. What is the pH of a sample of water if left to equilibriate with 2.0 ppmvof SO2 (KH= 1.2 mol L−1 atm−1)? Assume SO2 is the only acidic gaspresent.

7. Describe two physical features of lead that make it a functional materialand give an example of a common use.

8. PCBs can be destroyed by direct photolysis of the C−Cl bonds.

Ar− Clhν→ Ar ⋅+ Cl ⋅

Given that the average bond energy of C−Cl is 320 kJ mol−1, determinethe maximumwavelength of light that could be used to cleave this bond.


9. Describe two proposed methods to dispose of excess plutonium.

10. Construct and balance the equation where the PCBmolecule (C12H7Cl3)is destroyed by combustion with oxygen to yield CO2, H2O, and HCl.

Part B: Long-answer Questions

Themarks for each question are indicated in square brackets.

11. The whole body half-life of lead is six years. A 15 kg infant has a bloodlead level of 80 ppb. [Assume blood has the same density as water.]

a. What is the blood lead concentration (g per 100mL)? [4 marks]

b. Assuming the whole body concentration is the same as the bloodconcentration, calculate the total amount lead in this infant.[4 marks]

c. What daily intake (mg) of lead is required to maintain a steady-stateaccumulation of 3.0 mg? [5 marks]

12. The COD of a water sample is 25 mg of O2 per litre.What volume of0.0010mol L−1 Na2Cr2O7 solution is required to titrate a 40mL sampleto end-point? [Hint: The dichromate ion oxidizes 1.5 times the materialthat molecular oxygen does.] [13marks]

13. In your ownwords, briefly define five (5) of the following terms:[2 marks each]

in situBTXTOCbiomagnificationADIphytoremediationBODwater hardness[10marks]

14. Two commonmethods of secondary treatment of sewage are discussedin the textbook.

a. Briefly describe each of these twomethods. [10marks]

b. What is the main purpose of the secondary treatment stage?[4 marks]


Answers to Sample Final Examination

1. Circle H2O2, KMnO4, andHClO4

2. Ksp(PbSO4)=2.0×10−8=[Pb2+][SO42−]=x2

x=[Pb2+]=1.41×10−4

Mass(Pb)=Moles(Pb)×MWt(Pb)

=(1.41×10−4)(207.19 gmol−1)=2.93×10−2 g L−1=29.3 mg L−1

=29 ppm

3. A point source is a major known source of a pollutant (e.g., a largefactory). A nonpoint source is a combination of several potentialunknown sources each providing smaller amounts of pollution(e.g., farms).

4. Total Equivalent TCDD=Total Mass× (Wt% of Component X)(TEQ of X)

=(10.0 g)[(0.3)(0.5)+(0.45)(0.01)+(0.25)(0.1)]=1.795 g∴ 10.0 g of the mixture is equivalent to 1.8 g of 2,3,7,8-TCDD

5. CO2+H2Ov H2CO3

H2CO3 v HCO3−+H+

6. [SO2]=PNO2×KH=(2.0×10−6 atm)(1.2 mol L−1 atm−1)=2.4×10−6 mol L−1=[H2SO3]

H2SO3 v H+ + HSO3−

2.4× 10−6 0 0 (initially)2.4× 10−6−x x x (at equilibrium)

K1=1.7×10−2=(x2)/(2.4×10−6−x)x=2.40×10−6=[H+] (from quadratic formula)

pH=5.6

7. Lead’s properties include being malleable, and having a lowmeltingpoint and a high density. Common uses include ammunition, water ducts,piping, cooking vessels, solder, roofing, flashing, and soundproofing.


8. E=hc/(320,000 J)/(6.023×1023 atomsmol−1)=(6.626×10−34)(3.00×108m s−1)/ λ

λ=3.74×10−7 m∴maximumwavelength would be 374 nm

9. Proposal A:Mix excess plutoniumwith other radioactive wastes, vitrify,and then bury underground in metal canisters.

Proposal B: Convert excess plutonium to PuO2 andmix with uraniumoxide to produce a mixed oxide fuel (MOX) to be used as fuel in fissionreactors.

10. Unbalanced equation:

C12H7Cl3+O2 CO2+H2O+HClBalanced equation:

C12H7Cl3+13O2 12CO2+2H2O+3HCl

11. a. 80 ppb=(80 g/ 1×109 g)=8.0×10−8

Assume 100mL≡100 gMass(Pb) in 100mL=(8.0×10−8)(100 g)=8.0 mg∴ 8.0 mg per 100mL blood

b. Total Mass(Pb)=Concentration(Pb)×BodyMass=(8.0×10−8)(15 kg)=1.2×10−6 kg=1.2 mg

c. CSS=1.44Rt1/2(3.0 mg)=1.44R(6 y)Solve for R

R=0.47 mg y−1=9.5×10−4 mg d−1

12. Moles(O2)=Mass(O2)/MWt(O2)

=(0.025 g)/(32 gmol−1)= 7.81×10−4 mol (per litre water)Moles(O2) in 40mL

=(7.81×10−4 mol L−1)(0.040 L)=3.12×10−5 molMoles(Na2Cr2O7)=Moles(O2)/1.5

=(3.12×10−5 mol)/1.5=2.08×10−5 molMoles(Na2Cr2O7)=Molarity(Na2Cr2O7)×Volume(Na2Cr2O7)

(2.08×10−5 mol)=(0.0010mol L−1)×VV=2.08×10−2 L=20.8 mL


13. in situ: in the same place

BTX: benzene-toluene-xylene component of gasoline

TOC: total organic carbon

biomagnification: substance increases concentration along an ecologicalfood chain

ADI: acceptable daily intake, which in toxicological terms is typically1/100th of the NOEL

phytoremediation: the in situ remediation of soils through the use ofvegetation.

BOD: biological oxygen demand, which is a measure of the oxidizableorganic content of a water sample

water hardness: combined amount ofMg2+ and Ca2+ ions in a watersample

14. a. (1) Trickling filters use aerobic micro-organisms on sand/gravel bed,sprinkled with dirty water from a rotating boom. The aerobicbacteria feed on the carbon compounds and the entire setup takes lotsof space. (2) Activated sludge reactors use micro-organisms in atank. They chew up carbon compounds under aerobic conditionswith agitation. Activated sludge reactors are quicker than tricklingfilters.

b. reduce BOD

chemistry 330 environmental chemistry - athabascau.ca · 2 environmentalchemistry the myau portal...

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