Chemistry 330
Environmental Chemistry
Student Manual
Athabasca University a
Course Team
Course Coordinator: Lawton Shaw
Revisions: Lawton Shaw (2006)
Editor: Gilda Sanders
Visual Design: Ian Grivois
Web Design: Konrad Michalski
Visual Presentation: Athabasca University Digital Media Technology Unit
This course is a revision of an earlier version of Chemistry 330 prepared by
the following course team:
Author and Course Coordinator: Dietmar Kennepohl
Editor: Erna Dominey
Visual Design: Ian Grivois
Web Design: Konrad Michalski
Visual Presentation: Athabasca University Typesetting Unit
Every effort has been taken to ensure that these materials comply with the
requirements of copyright clearances and appropriate credits. Athabasca
University will attempt to incorporate in future printings any corrections
which are communicated to it.
The inclusion of any materials in this publication is strictly in accord with the
consents obtained and Athabasca University does not authorize or license
any further reproduction or use without the consent of the copyright holder.
E Athabasca University 2002, 2006
All rights reserved
Printed in Canada
CMID 537669
Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
The myAU Portal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Your Student ID Number . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
The Athabasca University Calendar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Course Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 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 and Writing Examinations . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Writing Essays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Intellectual Indebtedness and Plagiarism . . . . . . . . . . . . . . . . . . . . . . . . . 27
Transcripts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Credit Transferability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Sample Examinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Sample Mid-term Examination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Answers to Sample Mid-term Examination . . . . . . . . . . . . . . . . . . . . . . . 33
Sample Final Examination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Answers to Sample Final Examination . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Introduction
Welcome to Chemistry 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 for
environmental and human health.
Issues concerning our health and environment have become increasingly
important in recent years. Ozone depletion, the “greenhouse effect,” heavy
metal poisoning and acid rain are only a few controversial issues that have
come to the public’s attention through the media. Often, in discussions of
these phenomena, “facts” are (intentionally or unintentionally) misrepresented,
exaggerated, or taken out of context. It becomes difficult to weigh the
importance of much of this information when one is constantly bombarded
by media sensationalism.
It has become increasingly important for young scientists not only to be
aware of environmental and health issues, but also to be well informed about
them. Chemistry 330: Environmental Chemistry will provide a broad
overview of many important environmental issues. It will also give students
the most reliable and recent scientific information available, so that they may
draw independent and informed conclusions about these issues.
Environmental chemistry is a multidisciplinary subject with inputs from such
fields as meteorology, engineering, geology, ethics, politics, physics, medicine,
toxicology, and chemistry. Students enrolled in this course must have completed
Athabasca University’s Chemistry 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 the
course, the course materials, and the procedures that you should follow to
obtain the maximum benefit from your studies. Please read it carefully, and
keep it in a safe place.
Note: These course materials have been designed for students who are taking
the individualized-study version of this course. Students in a grouped-study
environment should follow the course outline, study schedule, and learning
activities provided by their instructor.
Chemistry 330 / Student Manual
1
The myAU Portal
MyAU is a personalized portal to the University where you may quickly
access information that is relevant to you, including on-line components of
your courses. Through myAU, you can view personal information, such as
library accounts and assignment marks and course grades, and take care of
administrative matters, such as booking examinations, submitting
assignments, applying for extensions, registering for courses, and so on.
Athabasca University will also communicate directly with you through
myAU. Check the Message Centre on your myAU home page for both
general 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 are
having browser difficulties or you need help, refer to myAU Help 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 other
contact with the University, you are asked to provide your student ID number.
Record this number in the space below. Having your student ID number helps
University staff to process your requests, grades, and administrative matters
more quickly.
Student ID number:
Note: The personal information and records collected and maintained by the
University as a result of a student’s registration in this course, such as
completed assignments and examinations, electronic communications, and
correspondence, are subject to University policies and the privacy and access
provisions of the Alberta Freedom of Information and Protection of Privacy Act.
The Athabasca University Calendar
Because Athabasca University’s policies, practices, and procedures change
over time, some of the information in this Student Manual may lose its
currency between course revisions. Students are therefore advised to refer to
the current Athabasca University Calendar on important issues concerning
University policies, procedures, and practices. In the event of any
discrepancy between the printed version of the Calendar and the official
Web-based Calendar, the Web-based version will be binding.
2
Environmental Chemistry
Course Materials
The package you received should include each of the items listed below. If
anything is missing from your package, please contact the Course Materials
division of Athabasca University as soon as possible. If you live in Calgary or
Edmonton, you can call the Learning Centre in your city and use the automated
telephone attendant to connect with Course Materials (the extension is 6366).
If you live within Canada or the United States, but outside of Edmonton or
Calgary, you can call the automated attendant by dialing 1.800.788.9041. If
you live outside of Canada or the United States, or if you do not wish to use
the automated system, you can call 780.675.6366. You can send electronic
mail to
cmat@athabascau.ca
or write to Course Materials, Tim Byrne Centre, 4001 Hwy 2 South,
Athabasca, AB T9S 1A4.
Textbooks
Baird, Colin, and Michael Cann. Environmental Chemistry, 3rd ed. New
York: W. H. Freeman and Company, 2005.
Baird, Colin. Student Solutions Manual for Environmental Chemistry, 3rd ed.
New York: W. H. Freeman and Company, 2005.
Note: Errata for the Student Solutions Manual are provided at the Web
site 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 as
a student.
You should spend a few minutes familiarizing yourself with these materials.
Chemistry 330 / Student Manual
3
The items listed below are not supplied; you should purchase them before
you begin to work on the course.
1. an electronic calculator, preferably a “scientific” calculator, capable
of handling logarithms and exponentials. Note: Remember to take your
calculator with you whenever you write an examination or attend a
laboratory 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, and
is equivalent to a one-semester course at a conventional university. It is
offered in individualized-study delivery mode, and is normally open to
students throughout the year. Students can determine their own timelines
for completing it, up to a maximum of six months. Nonetheless, they are
encouraged to follow the study schedule in this Student Manual. Students
who do so will have no difficulty in completing the course requirements
within the six-month contract period. However, students who find
themselves running short of time may purchase an extension to their
course contract. The Athabasca University Calendar contains information
on obtaining an extension to a course contract. You may wish to review this
information to ensure that you apply in a timely manner.
4
Environmental Chemistry
Course Design
Athabasca University course materials are designed for self-instruction
and study. What you should learn and how you should learn it are described
in the Study Guide. The Study Guide begins with a general chemistry review
unit. Each of Units 1 to 11 in the Study Guide corresponds to one chapter in
your textbook, Environmental Chemistry. Each Study Guide unit contains
an overview of the relevant textbook chapter, sections corresponding to the
subdivisions 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 the
Study Guide.
1. Every unit in the Study Guide begins with an Overview. It contains a
brief discussion that outlines the the textbook authors’ overall approach
to 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 valuable
features of the Study Guide, because they tell you explicitly what you
must understand and be able to do for each section of each unit.
Questions on the examinations and tutor-marked assignments are
based only on the section objectives. However, you should be aware
that many questions will require you to demonstrate mastery of a
number of related objectives, and you should not place too narrow an
interpretation 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 the
material effectively, additional information, and details of any errors
that occur in the textbook.
d. suggested exercises selected from those given at the end of each
chapter of the textbook. The purpose of doing these exercises is to
improve your understanding of the material you have just studied
and to develop your problem-solving skills. Refer to your notes and
to the textbook when you attempt these exercises. You will find the
answers in the Student Solutions Manual for Environmental
Chemistry, 3rd ed., by Colin Baird. Do make a concerted effort to
answer each question independently, but do not spend a large amount
of time on any one exercise: if you are unable to make any progress
after a few minutes of concentrated work, use the answers to help.
Many of the answers are laid out in stepwise fashion, and often, after
checking the first step, you will be able to proceed on your own.
Chemistry 330 / Student Manual
5
3. Each unit ends with the “Review Procedure,” a short list of steps that you
should take when reviewing the unit and completing any related
assignments.
There are four tutor-marked assignments in Chemistry 330. These assignments
contribute to the overall mark that you will obtain for the course (see the
section of this manual titled “Assessment of Students’ Work”).
The textbook, Environmental Chemistry, 3rd ed., by Colin Baird and Michael
Cann, contains most of the information you will need to pass this course. It is
a standard textbook used in several universities and colleges throughout
North America. It was chosen because it offers clear explanations and
interesting discussions of the material covered in this course.
6
Environmental Chemistry
Your Course Tutor
Athabasca University provides each student in each course with a tutor
whose responsibility is to help the student complete the course successfully.
A letter containing your tutor’s name, address, telephone number, electronic
mail address, and tutoring hours was mailed to you shortly before your
official start date. If you have not yet received your tutor letter, please contact
Learning Services—Tutorial at Athabasca University as soon as possible.
You can use the automated attendant (see the “Course Materials” section of
this manual for instructions, the extension is 6196); you can call
780.675.6196; or you can send electronic mail to
tutserv@athabascau.ca
Your tutor has excellent academic qualifications, and is committed to helping
students learning at a distance. He or she is available to answer your questions
about course content or how to approach a problem or an assignment, and can
direct you to the right person or department to help you with other problems
that may be hindering your progress in your course or program. In addition,
your tutor will be responsible for marking your assignments. In general, you
should call your tutor first with any queries about Athabasca University.
The tutor letter will help you become acquainted with your tutor and will
provide information about your tutor’s schedule. If you have not yet received
a call from your tutor, do not hesitate to make the first call yourself. If you
live in Canada or the United States, you can call your tutor, toll free, during
his or her tutoring hours, using the information provided in the tutor letter. If
you live outside of Canada or the United States, please refer to the tutor letter
and the current Athabasca University Calendar for information about calling
your tutor. You may find it useful to schedule a regular study period when
your tutor is available so that you can call him or her when questions arise. If
you are unable to take advantage of the regular tutoring hours, contact your
tutor or the course professor to determine whether alternative arrangements
can be made.
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 or
when you run into any special problem. We have found that students who
maintain regular contact with their tutors are most likely to be successful in
completing their courses, so do keep in touch.
When you mail an assignment to your tutor, be sure to attach a tutor-marked
exercise form, and to keep a copy, at least a rough draft, in case the original
goes astray in the mail. Allow several working days, in addition to mailing
time each way, before you expect to receive the graded assignment. If you
wish to submit your assignments electronically, contact your tutor to discuss
Chemistry 330 / Student Manual
7
appropriate formats. An electronic version of the tutor-marked exercise form
is 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 your
assignments over the telephone. Be sure to mention any questions you have
about the assignment or the grade.
Keep your tutor’s letter of introduction with your course materials, and use
the 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 staff
in charge of a given course. The course professor works directly with tutors
on both academic and administrative matters. If you have difficulties you
cannot resolve with your tutor, you may wish to speak with the professor
directly. You should also address any questions about final grade reports or
centrally marked examinations to the professor. He or she can also provide
general information about program planning and curriculum development.
The course professor welcomes students’ comments on the course.
8
Environmental Chemistry
Services to Students
Athabasca University offers a wide range of services to its students. Advisors
are available to assist students in planning their programs and selecting
appropriate courses. Counsellors assist students in improving their study
skills and clarifying their educational goals. You can reach an advisor or
counsellor in several ways: by dialling 1.800.788.9041 and asking to speak
with an advisor or counsellor; by visiting Athabasca University’s Central
Office in Athabasca, or the Learning Centre in Edmonton or Calgary; or by
referring to the FAQ section of the Ask AU Web site:
http://www.askau.ca
Students who are looking for information about student awards and advice
about obtaining financial assistance are asked to contact the Office of the
Registrar. You can do so by dialling 1.800.788.9041 and asking for the Office
of the Registrar, or by directing your query through
http://www.askau.ca
Note: Students may write examinations at the Athabasca University Central
Office in Athabasca, at one of the Learning Centres, or at the other locations
listed 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 in
identifying culturally appropriate services designed for Aboriginal students
or counseling that is sensitive to the challenges Aboriginal students face,
please contact the Centre for World Indigenous Knowledge and Research, by
telephone at 1.800.788.9041, extension 2064, or by electronic mail at
indigenous@athabascau.ca
Chemistry 330 / Student Manual
9
Library Services
The Athabasca University Library collection contains more than 140,000
books, many periodical titles, and a range of audio-visual resources. The
Library subscribes to over 100 online databases, providing full text access to
selected articles from more than 20,000 journals.
Athabasca University Library’s collection primarily supports Athabasca
University courses and programs. Materials found in the print and electronic
collections are available for use by our students, faculty, and staff for reference
and research purposes. Requests for library materials or services can be made,
by e-mail, phone, fax, or mail, 24 hours a day (contact information is provided
below). Responses to most requests are handled within 24 hours, or by the next
business day. Borrowed materials are normally mailed to the student’s home
address, 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’s Web 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 from Athabasca University
Library’s main Web 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 the
contents of the course materials package. Some Athabasca University course
Study Guides list “Supplementary Materials,” including books, journal
10
Environmental Chemistry
articles, or audio-visual materials, which students may find useful when
completing assignments and course projects. The supplementary materials
referenced in your course materials package are usually available from the
Athabasca University Library or your local library. Contact the Athabasca
University Library to request materials.
How the Library Gateway Works
The Library Web site contains the Library’s online catalogue (AUCAT), and
it is also the gateway to other online information. The Web site provides links
to journal databases and other subscribed online resources, as well as to
selected, publicly accessible Internet sites. Subscribed resources are available
to Athabasca University students, faculty, and staff. You will be required to
enter your first and last names as your username, and your student ID number
as your password.
The Library Web site also provides access to selected library catalogues from
Canadian public and academic libraries.
Interlibrary Loans
An interlibrary loan (ILL) involves one library borrowing materials from
another on behalf of a library user. Athabasca University Library will request
photocopies 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 of
publication, and page numbers) for the requested item. You are not required
to return these items to us. Allow sufficient time for the material to be
ordered and received. More information on the Interlibrary Loan process is
available on the Library Web site at
http://aupac.lib.athabascau.ca/screens/ill.html
Contacts
Athabasca University Library
1 University Drive
Athabasca, AB Canada T9S 3A3
Library web site: http://library.athabascau.ca
Email: library@athabascau.ca
Phone: 1.800.788.9041 (ext. 6254) Canada/US
780.675.6254 Other
403.263.6465 (ext. 6254) in Calgary
780.421.8700 (ext. 6254) in Edmonton
Fax: 780.675.6477
Chemistry 330 / Student Manual
11
Course Outline and Study Schedule
The table below gives a brief course outline and suggests the amount of time
that students should spend on each unit to complete the course in a 13-, 18or 26-week period. Students with a good background in chemistry and
mathematics should select one of the shorter schedules. The 26-week
schedule is primarily for students whose skills in chemistry and mathematics
need work.
Note: Students who are receiving financial assistance or those in a groupedstudy version of this course should check their course registration for special
restrictions on the length of registration, and should be prepared to adjust
their schedules.
Unit Textbook
Chapter
Title
Stratospheric Chemistry: The
Ozone Layer
2
2
Ground-Level Air Pollution—
Indoors and Ourdoors
3
3
The Detailed Chemistry of the
Atmosphere (TMA 1)
4
4
The Greenhouse Effect and
Global Warming
5
7
Toxic Organic Chemicals—
Pesticides (TMA 2)
1–5
1–4, 7 Review and mid-term exam
6
8
Nonpesticide Toxic Organic
Compounds of Environmental
Concern
7
9
The Chemistry of Natural
Waters
8
10
The Pollution and Purification
of Water (TMA 3)
9
11
Toxic Heavy Metals
10
12
Hazardous and Municipal
Wastes, and the Contamination
of Soils and Sediments
11
13
Radioactivity, Radon, and
Nuclear Energy (TMA 4)
Complete Term Paper
1–11 1–4, 7-13 Review and final exam
1
12
1
Environmental Chemistry
13-week
schedule
18-week
schedule
26-week
schedule
1
1–2
1–3
2
3–4
4–6
3
5
7
4
6-7
8-9
5
8
10-11
6
7
9
10
12
13–14
8
11-12
15–16
9
13
17–18
10
11
14
15
19–20
21–22
12
16
23–24
11–12
13
17
18
25
26
The following table is designed to assist you in planning a personalized study
schedule (with the help of your tutor). We suggest you begin by filling in the
first few units and keep track of how long each unit is taking you. After you
have done the first few units, you (and your tutor) should be able to come up
with a realistic schedule for the rest of the course.
Unit
Planned completion
date
Actual completion
date
Receive
course
Time required
(hours)
Action necessary
when completed
Contact tutor.
Unit 1
Unit 2
Unit 3
Complete TMA 1.
Unit 4
Request mid-term
exam.
Unit 5
Complete TMA 2.
Request mid-term
exam.
Write mid-term exam.
Unit 6
Unit 7
Choose term paper
topic.
Order material from
library.
Unit 8
Complete TMA 3.
Unit 9
Request final exam
Unit 10
Unit 11
Complete TMA 4.
Write term paper.
Write final exam
Chemistry 330 / Student Manual
13
Studying for this Course
Chemistry 330 is a three-credit course, and must be completed within the
six 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 that
you 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 your
background in first-year university chemistry. If your background is weak,
you may have to put in extra time, and this may affect your chances of
completing the course within the normal six-month contract period. If you
find that you really have trouble with Units 1 and 2, discuss the situation with
your tutor and consider withdrawing from the course, or taking some action
to improve your basic understanding of chemistry and mathematics.
At a traditional university, this course would normally take 12–13 weeks to
complete. If you wish to work at this rate, follow the 13-week study schedule
shown in the first table in the “Course Outline and Study Schedules” section
of 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 a major contributing factor to
ultimate success in this course. Should unforeseen circumstances put you in
a position where you find that you cannot complete the course within the
six-month contract period, you may request an extension. Check the
Athabasca University Calendar for the current regulations governing
extensions; there are time limits to which you must adhere.
We suggest that you start in on Unit 1 now. As you work through it, make a
note 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 in Chemistry 330, follow the procedure outlined below.
1. Read the overview at the beginning of every unit. At this stage, some
students find it beneficial to preview the unit by reading through the
whole 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 the
objectives and key terms as a guide when making notes.
d. reading the study notes (if any). These notes may contain study hints
or additional information, and will also identify any errors that occur
in the relevant section of the textbook.
14
Environmental Chemistry
e. completing the assigned exercises, and checking your answers in the
Student Solutions Manual for Environmental Chemistry, 3rd ed.
Note that your problem-solving ability will largely determine the
overall grade you receive in this course. The exercises represent the
minimum 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 your
tutor for grading.
Warning: With distance education, assignments may occasionally get lost in
the mail. As Athabasca University can only give credit for work that has
actually been received, we strongly advise that you keep a copy of all the
work that you submit to your tutor for marking.
Chemistry 330 / Student Manual
15
Assessment of Students’ Work
The assessment for this course is based upon examinations, tutor-marked
assignments (TMAs) and a term paper. Details can be found in the table
below. To obtain credit for Chemistry 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
Mid-term examination (2 hours)
Final examination (3 hours)
Tutor-Marked Assignments (TMAs)
Term paper
Units 1–5
Units 1–11
Units 1-3, 4-5, 6-8, 9-11
Essay topic
Percentage
of total mark
20%
40%
20%
20%
Both examinations are supervised and “closed book.” However, you will be
supplied with a periodic table and a list of appropriate data (constants, etc.).
You must be sure to have your own electronic calculator with you when you
write an examination. You should also take along a pencil, in case you are
required to draw a graph in any of the questions. There are no
multiple-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, it
may be possible for you to rewrite that examination. We strongly advise that
you consult the most recent edition of the Athabasca University Calendar to
obtain details of any recent or pending changes to the regulations governing
supplemental examinations. Any supplemental examination will be similar
in format to the first one, and the higher of the two marks will be used when
your overall course mark is determined. There is a fee for supplemental
examinations.
The following hints may help you to write examinations successfully.
1. Write the examination only when you and your tutor feel that you are
adequately prepared, and when you have successfully completed the
relevant tutor-marked assignments.
16
Environmental Chemistry
2. Remember that the examinations are based on the objectives outlined in
the Study Guide. Many of the questions will be similar in format to those
given in the tutor-marked assignments and in the examples given in the
section of this manual titled “Sample Examinations.”
3. For short answer questions, do the ones that you find easiest first. This
procedure has two benefits. First, you can more quickly accumulate
enough marks to pass the examination. Second, you gain confidence
to tackle the harder questions.
4. For numerical problems, show your work! Part marks will be given for
correct methods, even if your answer is incorrect.
5. The answers to numerical problems should be given to the correct
number of significant figures, and where appropriate, with the correct
units. Marks may be deducted if answers are given to an incorrect
number of significant figures or in the wrong (or no) units.
After you have written an examination, please be patient while you wait for
the result. Examinations rarely reach our central offices in less than five days,
and a ten-day lapse from when the examination is written to its arrival in
Athabasca is not unusual. Chemistry examinations are normally marked
within twenty-four hours of receipt, and your tutor is informed of the mark
before your next tutor night. Writing an examination one day and calling the
course professor a few days later does not expedite the marking process.
For security reasons, examinations cannot be returned to students, nor can the
professor enter into detailed discussions of specific examination questions.
After each of your examinations is corrected, some written comments will be
sent to you. Your tutor will also receive a copy of these comments, and you
should 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 the
course professor. If you still cannot obtain a satisfactory explanation of how
your grade was determined, please refer to the current Athabasca University
Calendar for information about the formal appeals procedure.
Chemistry 330 / Student Manual
17
Applying for and Writing Examinations
Before you write the final examination for this course, you must have
submitted all of your required course assignments and received feedback
from your tutor.
Although you do not require permission to apply for the examination, you are
advised to consult your tutor about your readiness to write it, and about
examination writing strategies. Your tutor can also provide information about
the examination format, and about study strategies.
To request an examination follow the steps below. Students in North America
must request examinations a minimum of 15 business days before the
intended writing date. Students elsewhere must allow additional time for
shipment of examination materials.
1. Review the “Evaluation” section of the current Athabasca University
Calendar.
2. Arrange for a time to write your examination with one of Athabasca
University’s Examination Centres or with an invigilator. For a list of
Examination Centres, see the Web site
http://www.athabascau.ca/registrar/invignet.php
If you would like to use an invigilator who has not been approved by the
Office of the Registrar, you may propose their approval by filling in the
appropriate details on the online Examination Request Form. Keep in
mind that invigilators may charge a fee, for which you will be
responsible.
3. Complete and submit the online Examination Request Form. If you do
not have access to the Internet, fill out the Examination Request Form
from your course materials package and submit it by fax (780.675.6174);
or in person or by postal mail to Examination Services, Office of the
Registrar, at Athabasca University’s central office.
Note: To minimize the time required to process your application, be sure
that you provide all of the information requested on the form, and that
you write legibly.
4. Confirm that your invigilator has received the examination package
before you arrive to write your examination. Take picture identification
and your student number with you when you go to the examination site.
The examination results and your final grade will be sent to you approximately
four to six weeks after you write the examination. The examination paper and
your booklets or answer sheets will not be returned to you.
18
Environmental Chemistry
To receive credit for the course, you must submit all the course assignments
and complete them to the satisfaction of your tutor. You must also obtain a
grade of 50 per cent or better on each course examination, and a course
composite grade of at least 50 per cent.
Supplemental Examinations and Appeals
Students who are dissatisfied with their grade on any examination, or who
obtain less than the required passing grade may write a supplemental
examination. The passing grade for supplemental examinations is
50 per cent, and only one supplemental is permitted per examination. The
higher of the two grades received will be recorded as the official grade. There
is a fee for supplemental services.
Appeals
Appeals to examination or assignment grades should be discussed first with
your tutor or instructor. For the correct procedure, see “Student Code of
Conduct and Right to Appeal Regulations” in the current Athabasca
University Calendar.
Chemistry 330 / Student Manual
19
Writing Essays
An essay written for a university course serves two main purposes. The first
and most obvious is pedagogical: researching a topic and writing about it is
an excellent way of learning. The second function served is evaluation: an
essay enables the instructor to assess the student’s ability to explain the
subject in a lucid and cogent fashion, to integrate the different types of
material covered, to analyse events or themes, and to place them in a
comprehensible order.
Although developing good essay writing skills is important, it need not be an
arduous task. A few basic principles that students must keep in mind are
listed below.
1. An essay should have an evident structure. Open your essay with an
introduction that states the problem you wish to explore or the question
you plan to answer. Examine the most important facets of the topic, and
discuss the issues that have been (or ought to be) the subject of scholarly
debate. Develop your own argument, and present your evidence in the
body of the essay. When your argument is complete and well presented,
end your work with a conclusion that summarizes the problem or
question and states your judgement or answer.
2. An essay should contain a well-developed argument and the evidence for
this intellectual position. It should contain a point of view, perhaps more
than one, expressed logically and supported by evidence that has been
appropriately documented; and it should lead to a conclusion that
appears natural and persuasive in the light of the evidence presented. An
essay must also contain a discussion and analysis of the material that is
balanced and judicious, taking opposing arguments into account, and
recognizing where the available information is insufficient or
inconclusive.
3. An essay must be based on adequate and appropriate reading and
reflection, and must acknowledge intellectual indebtedness through
proper citations. A superior essay should also show evidence of
individual thought: originality will be valued highly by the marker,
provided, of course, that the case is properly argued and not merely
eccentric.
Your grade will reflect how well you have met these standards. In attempting
to achieve these goals, you will develop and practise several intellectual
skills that will prove invaluable to you throughout your university career:
20
Environmental Chemistry
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 it
in context, and noting similarities to and differences from other writers’
presentations);
4. the habit of documenting, carefully and honestly, the sources of your
information 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 essay
writing. 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 you must follow to write a good essay.
Thoughtful, creative and well-argued essays may be organized in various
ways. However, if you need help with the mechanics of constructing essays,
the following suggestions will help you to organize and to write your
assignments.
Introduction or Thesis Statement
Begin your essay by stating the problem, issue or topic that you are going to
address in the paper, and outline the approach you are going to take in dealing
with it. This initial paragraph is sometimes called a ”thesis statement.” A
thesis statement is a sentence or series of sentences that defines a subject and
a particular position on or understanding of that subject. To construct a thesis
statement, you must have a general understanding of the topic and a
considerable amount of detailed and specific knowledge of the material; and
you must have thought through what you are going to say in the paper. You
must have considered each argument that supports your view and each
argument that undermines it. You must also have analysed the most
reasonable means of presenting your argument. So, although you only need
to provide a single statement, to produce that statement you must (a) know
the parameters of the question; (b) know the specific vocabulary that
describes 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 in
nature. As you continue to analyse your material, your approach may well
Chemistry 330 / Student Manual
21
shift. Keep the statement in mind, but be flexible. Do not reject information
or fail to include it because it disproves your statement. The statement you
begin with may change several times as you progress. You may find yourself
reorganizing the order of the material, shifting the discussion or changing
your position. Do not be alarmed by this process: it is an indicator that you
are thinking and coming to grips with your material. You may find that you
end up writing the final version of your introduction after you have
completed the main body of your paper.
Organization
Most people find it useful to construct an outline of the main components of
the paper, and then follow the outline when writing the text. The statement
of organization is a short passage that follows your thesis statement and
explains how you will analyse the topic and present your arguments. It helps
you clarify how you will prove and document your ideas, and it serves your
reader 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 the
introduction or the conclusion, and will normally contain several different
topics and discussions. As you sketch an outline, the main body of the essay
will expand to accommodate these various sections. Consequently, your
essay outline may at some point look like this:
I. Introduction
1. Interesting opening sentence (background, quotation, something to
interest and entice the reader)
2. Thesis statement
3. Statement of organization (the order of the points you will make to
justify 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
22
Environmental Chemistry
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 main
topics covered)
3. Overall conclusion based on evidence presented
With a complete and thoughtful outline, the writing of the essay is simply a
matter of fitting the research you have done into the pattern that you have
made. Just follow the outline, making sure that the progression of information
is logical and that your arguments are well supported by evidence and
analysis.
Editing
In writing a final draft, the quality of language and the logic of the argument
are the principal concerns: by the final draft, there should be no factual,
grammatical or spelling errors. Producing the final draft is a matter of
refining 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, an
object), and that the preceding and following sentences are linked and
logical. Examine each section of the essay for clarity and coherence. You
might ask yourself the questions listed below.
1. Introduction: Is it interesting? Is the thesis statement clear? Does it define
the exact subject and express a point of view? Does the statement of
organization cover all the topics?
2. Main Body: Does each paragraph cover a different point? Is it relevant to
the thesis? Does it have a topic sentence? Are details present, and do they
support the topic sentence, and in turn, the thesis? Does it provide proper
references? Does it contain a rich vocabulary?
Chemistry 330 / Student Manual
23
3. Conclusion: Does it restate the thesis? Does it provide a summary of the
material? Does it present a clear, valid conclusion?
The second type of editing is copy editing, and is effectively done line-byline, from the end to the beginning of the document. As you copy edit, you
check 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 a
few large, obvious ones. Good copy editing is a difficult task for an author. A
different pair of eyes, coming fresh to the text, will normally pick up
typographical errors that you have missed simply because you are too
familiar with your own work to notice them. Therefore, if you can find
someone else to help you read your final draft, you will almost certainly end
up with a cleaner, more error-free, manuscript. An alternative strategy is to
put your final draft in a drawer for a couple of days before attempting to copy
edit it yourself. Even if time pressure precludes this option and you have
nobody available to help you, it is important that you do your best to copy
edit your paper. Copy editing is the last stage of the essay writing process. It
will be very evident to your reader if you have not taken the trouble to finish
the job properly.
References
When you write an academic essay, it is sometimes difficult to know when to
reference information. A general rule is that a well-known textbook may be
considered a baseline. Everyone has access to it, and so the information in it
can be considered common knowledge. In-text citations, footnotes or
endnotes are necessary whenever you use material from another source.
It is important to document figures, dates, and specific events as well as
ideas. Of course, every fact and idea in the essay could be referenced, so you
have to make judgements about what it is necessary or reasonable and useful
to document. Knowing when to reference another source is a skill that you
will 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 product
of your thinking and should be written in your own words. You may,
however, come across a passage in your reading that expresses perfectly
an idea that you think is necessary to include. Simply to copy another
writer’s text into your essay without acknowledging the source is
plagiarism. In academic circles plagiarism is considered a grave offence,
and can lead to serious consequences. You may, however, copy the
passage and acknowledge the source in a reference. If the quotation is
24
Environmental Chemistry
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 a
more general manner. For example, you may have summarized in one
paragraph the main ideas and arguments of a scholarly paper that you are
listing in your bibliography. Even if you have employed no direct
quotations, it is customary to have a reference at the end of the paragraph
indicating the source of the information contained therein.
3. Similarly, if you are discussing (in your own words) several alternative
interpretations of a topic or controversial issue you can (and should) use
references to indicate to your reader the books and articles in which each
of these interpretations has been advanced. Often the way in which a
topic or issue is conceptualized, and the terms that are employed to
discuss it, implicitly suggest an interpretation or perspective on the
subject. Different authors use the same or similar terminology, but they
mean something different by those same words.
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 for
your essay:
1. an in-text citation, which provides the name of the author, the date, and
the page number, if applicable, in parenthesis; for example (Thompson
1990: 161).
2. a small superscripted Arabic number, presented at the end of the
phrase 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 the
page; for example, “. . . economic valorization of symbolic forms.”*
Whichever style of notation you choose, provide a full bibliographic
reference. When using in-text citations, gather your information together in a
reference list at the end of the essay. For example, a reference to Thompson in
the essay (Thompson 1990: 161) would be included in the reference list:
Thompson, John B. Ideology and Modern Culture. Stanford, CA: Stanford
University 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.
Chemistry 330 / Student Manual
25
4. When using either footnotes or endnotes, the number refers to the
material that appears at the bottom of the page (footnotes) or on a
separate page at the end of your essay (endnotes). The first time you refer
to a book, you should provide full bibliographical reference:
1. John B. Thompson, Ideology and Modern 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 an
explanation that would otherwise interrupt the flow of the argument, to
explain a foreign word or phrase, or to give additional biographical
information. However, if you find that you are using explanatory notes too
often, you should rethink your outline. Generally, if something is important
enough to be included in your essay at all, it should find an appropriate place
in 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 all
the 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 quoted
or cited. The list should be arranged alphabetically by the first author’s
surname and initials. The Study Guide contains suitable examples.
Note: When you prepare your bibliography, you may underline the title of a
book or use italics; do not do both.
Essay Presentation
For the convenience of your tutor, leave fairly wide margins. They facilitate
the insertion of corrections and comments, and make your essay easier to read
(a decided psychological advantage). The ideal margins are approximately four
centimetres at the left and two and one-half centimetres at the top, bottom and
right-hand side. Whether you are typing or writing in longhand, please
double-space your paper. Before submitting your essay, be sure to proof-read
it carefully to catch any spelling mistakes, typing errors and the like. Do not
write in pencil.
Last but by no means least, please keep a copy of your paper (at least the
rough draft), just in case the original should go astray in the mail.
26
Environmental Chemistry
Intellectual Indebtedness and Plagiarism
Students enrolled in any Athabasca University course are considered to be
responsible scholars, and are therefore expected to adhere rigorously to the
principles of intellectual honesty. Plagiarism is a form of intellectual
dishonesty in which another’s work is presented as one’s own, and, as will
any form of academic misconduct, plagiarism will be severely penalized.
Depending on the circumstances, penalties may involve rejection of the
submitted 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 and
secondary—in a full and consistent manner. All direct quotes (quotations,
however short, from an original work) and indirect quotes (paraphrases of ideas
presented in an original work) must be acknowledged. There are three
conventional ways of acknowledging your sources: in-text citations,
footnotes, or end-notes. We prefer that you use in-text citations, combined
with a full bibliography presented at the end of the essay. The in-text citation
must give the name of the author, the date of publication, and the page on
which the cited material appears (Doe, 1997, p. 60). The bibliographic entry
must provide at least the author’s last name, first name or initial, the date of
publication, the title of the work, the place of publication and the publisher.
For further information, see the section of this manual titled “Writing
Essays.”
Dutiful citation of quotes and paraphrased material does not mean you can
write an essay assignment by stringing together a series of quotes. You
should always try to summarize or describe someone else’s ideas in your
own words. If you present your own ideas or opinions in a paper, provide
substantiated evidence or arguments for your position.
All assignments must be original work for this course. The use of
assignments from previous courses or from other students is considered a
form of cheating and will be subject to discipline for academic misconduct.
For more information on this important matter, see the Athabasca University
Calendar.
Chemistry 330 / Student Manual
27
Transcripts
A student can request an official transcript by completing a paper “Transcript
Request” form, by writing to the Office of the Registrar, by appearing at the
Office of the Registrar in person, or by using the secure on-line request form.
For instructions on making an on-line request, please see
http://www.athabascau.ca/registrar/transcripts_FAQ.php
Only the student whose transcript is being issued may make the request, and a
paper request must bear the student’s signature.
No partial transcripts are issued. The student’s entire record is shown on each
transcript.
Most institutions and agencies require that official transcripts be sent directly
from Athabasca University. Please allow a minimum of ten working days for
the receipt of a transcript. Consult the current edition of the Athabasca
University Calendar for further information about transcripts.
Credit Transferability
If you wish to transfer credit to another institution, contact the Office of the
Registrar at Athabasca University. Remember, however, that transfer of credit
is determined by the receiving institution. If you plan to transfer Chemistry 330
to another institution, we suggest you get an agreement, in writing, from that
institution.
28
Environmental Chemistry
Sample Examinations
On the following pages you will find sample examinations that will help you
to prepare for your mid-term and final examinations. We have included such
questions in this manual to give you a better idea of the length of a normal
Athabasca University chemistry examination. Short answers are given for
most of the questions, and can be found at the end of the sample
examinations.
Chemistry 330 / Student Manual
29
30
Environmental Chemistry
Sample Mid-term Examination
The mid-term examination is two hours long. As you write the examination,
you may not consult any books or notes. However, the use of a calculator or
slide rule is permitted. You will also be provided with a periodic table and a
set of standard physical constants (i.e., a data sheet).
Part A: Short-answer Questions
Each question in this section is worth 3 marks.
[30 marks]
1. Complete the following table.
Radiation Type
Spectral Range Primary Absorber of Sunlight
(nm)
UV-A
320–400
280–320
NO2
UV-C
O2 and O3
2. Write the two-step noncatalytic photochemical reactions for the
destruction of stratospheric ozone. (Hint: Last half of the Chapman
mechanism.)
3. The rate constant for
OH+O3  HO2+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 would
absorb infrared radiation.
Ar
O3
Cl2
CO2
H2
CF4
7. The atmosphere contains 3.9×1015 tonnes of nitrogen gas. Annual
losses of nitrogen include thunderstorms (6.9×107 tonnes) and nitrogen
fixation by bacteria (2.1×108 tonnes). Calculate the residence time of
nitrogen in the atmosphere.
Chemistry 330 / Student Manual
31
8. For DDT, log Kow = 6. What is the approximate bioconcentration factor
for DDT in fish?
9. Draw the general structure of a carbamate.
10. Hydroxyl radicals are key in the oxidation of hydrocarbons in the
troposphere. Compare the first step (i.e., OH attack) in the oxidation of
methane 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 0.00124 mg 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 the
troposphere, but increases with altitude in the stratosphere. [10 marks]
13. The rate constant for the attack of methane by the hydroxyl radical is
about 3.6×10−15 cm3 molecule−1 s−1. Assume that
[OH]=8.0×105 molecule 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, how many
tonnes of CH4 is removed each year? [8 marks]
14. In your own words, briefly define five (5) of the following terms.
[2 marks each]
fuel cell
VOC
phenoxy herbicide
nitrification
homonuclear diatomic molecule
enhanced greenhouse effect
acid rain
CFC
[10 marks]
32
Environmental Chemistry
Answers to Sample Mid-term Examination
1. Complete the following table.
Radiation Type
Spectral Range Primary Absorber of Sunlight
(nm)
UV-A
320–400
280–320
200–280
UV-B
UV-C
NO2
O3
O2 and O3
2. O3+h (<320 nm) → O2+O
O+O3
→
2O2
3. Arrhenius equation
k=Ae(− Ea/RT)=1.9×10−12e(−1000/T)
By inspection we notice that
Ea/RT=1000/T
Solve 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, cement
additive, roofing and pipes, and fireproof clothing.
6. CO2, O3, and CF4 should be circled because they can absorb infrared
radiation.
7. Tavg = C/R
= (3.9×1015 tonnes)/( 6.9×107+2.1×108 tonnes y−1)
= 1.4×107 y
8. log Kow = 6, so Kow = 1,000,000. For fish, Kow serves as a reliable
approximation for BCF. Hence, BCF  1,000,000.
Chemistry 330 / Student Manual
33
9. General structure of carbamate:
O
H
N
O
R
CH3
10. Hydrogen abstraction:
a. CH4+OH  CH3+H2O
b. OH Addition:
c. H2C=CH2+OH  H2C−CH2(OH)
11. a.
solubility =
0.00124 mg
0.2000 L
= 0.00620 mg∕L
= 0.00620 ppm
b. molar mass HCB = 284.76 g/mol
n=
0.00124 mg
284.76 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 infrared
radiation emitting from the Earth’s surface. Increased distance from the
surface results in a lower temperature. However, in the stratosphere a
temperature inversion occurs through increased occurrence of ozone
formation
O+O2+M  O3+M (heat released)
which is in turn controlled by incoming sunlight (<241 nm). Together
these processes determine the temperature profile and therefore the
distinction between troposphere and stratosphere.
34
Environmental Chemistry
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 molecules
Moles(CH4)=molecules/N
=(1.76×1037 molecule)/(6.022×1023 molecule mol−1)
=2.93×1013 mol
Mass(CH4)=Moles(CH4)×Molecular Weight(CH4)
=(2.93×1013 mol)(16 g mol−1)
=4.69×1014 g or 4.69×1011 kg or 4.69×108 tonnes
14. fuel cell: primary electrochemical cell in which reactants are
continuously supplied from outside
VOC: volatile organic compound (e.g., butane)
phenoxy herbicide: a class of herbicides made by reacting a phenoxide
anion with an alkyl halide (e.g., 2,4--D)
nitrification: reduced nitrogen is oxidized (e.g., NH3  NO3−)
homonuclear diatomic molecule: two-atom molecule having the same
atoms (e.g., N2 or Cl2)
enhanced greenhouse effect: increased trapping of thermal infrared
energy 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 of
environmental interest because of their damaging effect on stratospheric
ozone.
Chemistry 330 / Student Manual
35
Sample Final Examination
The final examination is three hours long. As you write the examination, you
may not consult any books or notes. However, the use of a calculator or slide
rule is permitted. You will be given a periodic table and a set of standard
physical constants (i.e., a data sheet).
Part A: Short-answer questions
Each question in this section is worth 3 marks.
[30 marks]
1. Circle all species below that are considered common oxidizers in
hazardous waste.
H2O2
CH3CH2CH3
CaSiO4
NH3
KMnO4
HClO4
2. Calculate the equilibrium concentration (in ppm) of Pb2+ in water sitting
over 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 the
following 10.0 g mixture of dioxins?
Dioxin Weight %
A
B
C
30
45
25
TEQ
0.5
0.01
0.1
5. Write down the chemical equation that illustrates that water exposed to
carbon dioxide is acidic.
6. What is the pH of a sample of water if left to equilibriate with 2.0 ppmv
of SO2 (KH = 1.2 mol L−1 atm−1)? Assume SO2 is the only acidic gas
present.
7. Describe two physical features of lead that make it a functional material
and give an example of a common use.
8. PCBs can be destroyed by direct photolysis of the C−Cl bonds.
hν
Ar − Cl → Ar ⋅ + Cl ⋅
Given that the average bond energy of C−Cl is 320 kJ mol−1, determine
the maximum wavelength of light that could be used to cleave this bond.
36
Environmental Chemistry
9. Describe two proposed methods to dispose of excess plutonium.
10. Construct and balance the equation where the PCB molecule (C12H7Cl3)
is destroyed by combustion with oxygen to yield CO2, H2O, and HCl.
Part B: Long-answer Questions
The marks 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 blood
lead level of 80 ppb. [Assume blood has the same density as water.]
a. What is the blood lead concentration (g per 100 mL)? [4 marks]
b. Assuming the whole body concentration is the same as the blood
concentration, calculate the total amount lead in this infant.
[4 marks]
c. What daily intake (mg) of lead is required to maintain a steady-state
accumulation of 3.0 mg? [5 marks]
12. The COD of a water sample is 25 mg of O2 per litre. What volume of
0.0010 mol L−1 Na2Cr2O7 solution is required to titrate a 40 mL sample
to end-point? [Hint: The dichromate ion oxidizes 1.5 times the material
that molecular oxygen does.] [13 marks]
13. In your own words, briefly define five (5) of the following terms:
[2 marks each]
in situ
BTX
TOC
biomagnification
ADI
phytoremediation
BOD
water hardness
[10 marks]
14. Two common methods of secondary treatment of sewage are discussed
in the textbook.
a. Briefly describe each of these two methods. [10 marks]
b. What is the main purpose of the secondary treatment stage?
[4 marks]
Chemistry 330 / Student Manual
37
Answers to Sample Final Examination
1. Circle H2O2, KMnO4, and HClO4
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 g mol−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 large
factory). A nonpoint source is a combination of several potential
unknown 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+H2O
H2CO3
v
v
H2CO3
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
2.4 × 10−6
2.4 × 10−6−x
H+ +
HSO3−
0
x
0
x
(initially)
(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 low melting
point and a high density. Common uses include ammunition, water ducts,
piping, cooking vessels, solder, roofing, flashing, and soundproofing.
38
Environmental Chemistry
8. E=hc/
(320,000 J)/(6.023×1023 atoms mol−1)
=(6.626×10−34)(3.00×108 m s−1)/ λ
λ=3.74×10−7 m
∴ maximum wavelength would be 374 nm
9. Proposal A: Mix excess plutonium with other radioactive wastes, vitrify,
and then bury underground in metal canisters.
Proposal B: Convert excess plutonium to PuO2 and mix with uranium
oxide to produce a mixed oxide fuel (MOX) to be used as fuel in fission
reactors.
10. Unbalanced equation:
C12H7Cl3+O2  CO2+H2O+HCl
Balanced equation:
C12H7Cl3+13O2  12CO2+2H2O+3HCl
11. a. 80 ppb=(80 g/ 1×109 g)=8.0×10−8
Assume 100 mL≡100 g
Mass(Pb) in 100 mL=(8.0×10−8)(100 g)=8.0 mg
∴ 8.0 mg per 100 mL blood
b. Total Mass(Pb)=Concentration(Pb)×Body Mass
=(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 g mol−1) = 7.81×10−4 mol (per litre water)
Moles(O2) in 40 mL
=(7.81×10−4 mol L−1)(0.040 L)=3.12×10−5 mol
Moles(Na2Cr2O7)=Moles(O2)/1.5
=(3.12×10−5 mol)/1.5=2.08×10−5 mol
Moles(Na2Cr2O7)=Molarity(Na2Cr2O7)×Volume(Na2Cr2O7)
(2.08×10−5 mol)=(0.0010 mol L−1)×V
V=2.08×10−2 L=20.8 mL
Chemistry 330 / Student Manual
39
13. in situ: in the same place
BTX: benzene-toluene-xylene component of gasoline
TOC: total organic carbon
biomagnification: substance increases concentration along an ecological
food chain
ADI: acceptable daily intake, which in toxicological terms is typically
1/100th of the NOEL
phytoremediation: the in situ remediation of soils through the use of
vegetation.
BOD: biological oxygen demand, which is a measure of the oxidizable
organic content of a water sample
water hardness: combined amount of Mg2+ and Ca2+ ions in a water
sample
14. a. (1) Trickling filters use aerobic micro-organisms on sand/gravel bed,
sprinkled with dirty water from a rotating boom. The aerobic
bacteria feed on the carbon compounds and the entire setup takes lots
of space. (2) Activated sludge reactors use micro-organisms in a
tank. They chew up carbon compounds under aerobic conditions
with agitation. Activated sludge reactors are quicker than trickling
filters.
b. reduce BOD
40
Environmental Chemistry