Unit Of Practice
The Mole
Unit Of Practice
Abstract
This
is a hands-on inquiry based unit on the mole.
This
is a project in which students will learn about the mole. It contains fun inquiry based activities and PowerPoint
presentation on the topic.
Students
will be working in a laboratory classroom everyday for a fifty-minute period
for one month.
Tasks
Activity 1:
Teacher notes:
Exploration
Activity
Inner Space
Lab
time - 1 class
Process
skills - formulating models and inferring
Objective:
The objective of this activity is to provide a situation in which
information regarding internal structure may be discovered without the luxury
of direct observation.
Materials:
12 sealed boxes, each containing one marble and various wooden shapes
glued to the box bottoms. Attached are suggested arrangements.
Teaching
strategies:
The "atomic boxes" are constructed from empty check boxes or
any other smaller size boxes, scrap wood shapes, and one marble per box.
Make certain that the boxes are not too flat or students will squeeze
the box and be able to "feel" the shape inside.
The 12 numbered or lettered boxes are to be placed throughout the room
and students are to follow the instructions under the procedure heading.
To ensure a degree of success, the students would be instructed on the
orientation of the boxes (which side is the bottom, the side with the glued-on
shapes) and could be provided with a sheet depicting the twelve different
arrangements.
Alternatively, an overhead transparency of the twelve arrangements
could be displayed during the activity. I usually let the students experiment
first before I put up the overhead with the internal patterns they can choose
from. Each group member should be encouraged to contribute opinions as to the
internal structure of the unknown box, and sharing between groups by using a
white board can make this a cooperative effort.
It is interesting to note that some students are able to
"sense" the internal structures quite easily while others have great
difficulty picturing the box contents.
Summing
Up:
1. Answers will vary.
2. Objects within the
boxes that would be difficult to detect might include extremely small objects
(air molecules, smaller bits of matter, etc.), symmetrical objects near the
box boundaries (like a strip of wood running completely along one side), flat
objects (like a piece of paper or a coin), and objects not on the box bottom.
3.
Students
were not able to "see" inside the boxes, just like scientists were
not able to directly observe what is inside the atom.
Adapted from a suggestion by George McKelvy in the October 1988 Science
Teacher and incorporated the Cristal Resources by Iowa Chemistry Task Force.
Student Laboratory Sheet:
Inner
Space
Exploration
Problem:
How do researchers learn about atomic structure even when they are
unable to directly observe what they are studying?
Materials:
sealed "atomic box" containing one "alpha marble"
Procedure:
You have been given one of twelve different lettered "atomic
boxes", each containing objects of varying size, shape and location.
Also contained within each box is an "alpha marble", which
will assist you in determining the internal structure of your "atomic
box". Note which lettered
box you are examining. You now
have five minutes to find and describe the shape(s) of the object(s) (nucleus)
in the box (atom). Sketch what
you believe to be the internal structure of your "atom".
After five minutes, examine a different box.
After another five minutes, exchange one more time so that each group
will have investigated three boxes. Make
sure you record the letters of the boxes you examine.
Summing
Up:
1. Summarize your findings
with a sketch, including the size, shape, and location of the objects in each
box you examined.
2. What types of objects
within the boxes would be impossible to detect using this technique?
3. How does this
experiment show the difficulties scientists encountered in discovering what
were inside the atom?
Activity 2:
Teacher Notes
Rice-O-Rama!
Exploration
Lab
time: 1 class
Process
skills: interpreting data and
experimenting
Objective:
By completing this investigation, students will gain experience in
"counting" large numbers of objects and thereby learn to count by
weighing.
Materials:
Prepare a number of containers of very small uniform objects. (I’ve
found very tiny beads in a film canister works well.)
Predetermine the number of objects in each container prior to class.
Metric
balance
Graduated
cylinders
Rulers
Teaching
Strategies:
It is important that you have so many objects that students will not be
tempted to count the objects individually.
Encourage students to try more than one method of "counting".
You may have to provide them with a hint or encourage them to look
around at what other students are trying.
Encourage creativity!
Summing
Up:
1. One method could
involve using a graduated cylinder and filling it with the objects to be
counted to the 1mL mark. The
number of items comprising 1mL can then be easily counted.
The total volume of the objects can then be measured using a large
graduated cylinder and the number of items calculated.
A second method could involve weighing a given number of items, say
25-50, and then weighing the entire sample.
The total number of items can then be calculated.
2. The advantage of
measuring the volume of the objects is that it is relatively easy and fast.
The disadvantage is that it may not be that accurate since there will
be variable space between the particles placed into the graduated cylinder.
In addition, all of the objects may not be of uniform size and this
could cause error in the counting process.
The advantage of using the mass to determine the number of items is
that it is both simple and accurate. The
disadvantage is that, again, particles of non-uniform size could cause errors
in estimating the number of objects in the sample.
3. Massing the objects
will likely yield the most accurate results since the packing of the objects
together is not a factor in this method of measuring.
Student Laboratory Sheet
Rice-O-Rama!
Exploration
Problem:
What are some different ways that can be used for "counting"
large numbers of objects?
Materials:
Containers with large number of small uniform objects, metric balance,
rulers, graduated cylinders and beakers
Procedure:
Obtain a container with objects from your instructor.
Your job will be to determine the number of objects in the container. Experiment with a number of different methods of counting.
Keep accurate notes of any counting methods attempted.
Summing
Up:
1. Write a description of
each of the counting methods you tried for the objects.
Describe at least 2 different methods.
2. List the advantages and
disadvantages of each counting method used.
3.
Of
the counting methods used, which do you believe to be the freest of error?
Why?
PowerPoint Presentation: See
attachment
Video: "The Atom" and "The Mole” from the World of
Chemistry
Students
will be able to answer the following questions:
1.
Scientists view objects that are too small to see with the naked eye by
using_______________.
2.
Like charges____________.
3.
A neutral atom has_____________numbers of positive protons and negative
electrons.
4.
In the Rutherford experiment positively charged particles were
deflected because they approached the__________________.
5.
Subatomic particles that are found in the nucleus of the atom
are____________and______________.
6.
The fuzzy cloud in the video graphic represents the space around the
nucleus occupied by the_________________.
7.
The nucleus is ___________________times smaller than the atom.
8.
The source of most of the lead in the atmosphere is______________.
9.
List two ways that knowledge of the atom is applied in the real world.
10.
The scanning tunneling microscope shows images of the ___________.
1.
It was the study of___________of reacting gases that provided the first
steps toward understanding the number relationship that exists between
molecules when they react.
2.
Avogadro said that equal volumes of different gases contained the same
number of molecules as long as they were measured at the same temperature
and_________________.
3.
By comparing the masses of two equal volumes of gases measured under
the same conditions, we have the ratio of the __________of individual
molecules.
4.
A mole of carbon has a mass of 12______________.
5.
Moles of different substances all have different masses from one
another but they all contain the ____________number of particles.
6.
Atomic masses in the periodic table are all__________masses based on
assigning carbon a mass of 12.0000 units.
7.
Using relative atomic masses, the equation will also tell us the
____________of reactants needed and products formed.
8.
At the start of the experiment each flask contained ____________moles
of hydrogen chloride.
9.
At the start of the experiment each balloon contained different amounts
of ______________.
10.
Epoxies are known for their excellent strength and _____________.
11.
The
mass of a mole of any element is its _____________ mass or its relative mass
in grams.
Activity 3
Teacher Notes
Bean
Salad
Concept
Development
Objective:
Students will simulate the process of how atomic amasses are
determined. This will help
students to realize why atomic masses are not whole numbers.
Teaching
Strategies:
Make sure that the students understand these analogies:
*
Each bean type = a different isotope of the element.
*
g/bean (grams per bean) = average mass of each bean = mass of each
individual isotope
*
Weighted mass of isotopes = atomic mass of the element
Some variation will result if there is a disproportionate amount of a
larger massed bean. (See attachment for sample data)
This disproportion will result in a skewing of the average mass of all
isotopes = atomic mass of the element.
You may need to explain some of the following ideas to your students.
But don't be hasty. Let
them experiment with their own ideas before providing them with this
additional information. All
atomic masses are relative masses. Carbon
#12, atomic mass = 12.0000 amu. is the standard mass to which all other atomic
masses are compared. For this
activity our standard mass will be the mass of 1 mL of water at 4C or 1.0000g.
Students may follow a procedure such as the one described below:
1)
Record the total number of each different type of atom in a data table.
2)
Calculate the atomic mass of each isotope by:
a) Finding the total mass for each isotope and recording that in your
data table.
b) Dividing the total mass of each isotope by the number of atoms in
your sample to find an average of a single atom.
3)
Divide the number of atoms of each isotope by the total number of atoms in the
baggie. Repeat this for all the
isotopes, recording your data in the data table.
4)
Using the method of weighted averages; the atomic mass can be determined based
on your data. Atomic mass = %
isotope (1) x mass of one atom of isotope (1) + % isotope (2) x mass of one
atom of isotope (2) +.... n
Student Lab Sheet
Bean
Salad
Problem:
1) How can you determine the percent abundance of each isotope in a
sample of an element? 2) How can you determine the atomic mass for an element from
percent abundance?
Procedure:
Isotopes are atoms of an element, which are chemically the same, but
have different physical properties. Isotopes
differ in their atomic masses. Since
atoms are very small we will substitute a larger item, a bean, to represent
the different isotopes of our element. In
this activity you will be using different types of beans.
Each bean represents an isotope of the new element pintonium.
Using the masses of your beans, find the average atomic mass of your
element, pintonium. Be sure to
show all of your calculations in answering each of the questions below.
Summing
Up:
1.
How many different isotopes were in the container?
2.
What was the total mass of each group of isotopes?
3.
What is the atomic mass of each isotope?
4.
What were the percent abundances for each isotope in the entire sample?
5.
What was the weighted average atomic mass of your sample?
6.
A student obtained the following data when measuring a sample of
element X:
Isotope # of atoms
Mass of sample
A
40
400
B 160
1760
Calculate
the following:
a)
Percent composition of each bean.
b)
Mass of each isotope.
c)
The atomic mass of element X.
What
is the name of element X?
Activity 4
Teacher Notes
How
Many Molecules of Water Are in Lake Erie?
Concept
Development
Lab
time: 1 day
Objective:
By completing this activity students will be able to determine the
number of water molecules in Lake Erie. They
will utilize the factor-label method to make difficult calculations by
breaking a problem down into intermediate steps.
Teaching
Strategies:
Students will first need to determine experimentally the number of
drops of water in 1 mL, but let them figure this out on their own!
Drops should be of uniform size. With
the use of a balance, students should then determine that 1 mL of water has a
mass of approximately 1 g. If
needed, review the factor-label method in making calculations.
For simplicity, tell students to assume that Lake Erie is essentially a
rectangular block so they can successfully calculate the volume. (See
attachment for sample data)
Adapted
from an idea described in The Science Teacher and adapted by Cristal.
Student Lab Sheet
How
Many Molecules of Water Are in Lake Erie?
Problem:
How do you determine the number of molecules of water in Lake Erie?
Procedure:
Utilizing the equipment listed above and the following information,
determine the number of molecules of water in Lake Erie.
Helpful
Information:
*One
mole of anything contains 6.02 x 23 units.
*One
mole of water has a mass of 18.02 grams.
*Lake
Erie has an average depth of 18 m.
*Lake
Erie covers 2.6 x 104 km squared.
Hold
it a minute! Are you sure that
you have all of the information you need?
There might be more data needed from the lab.
Think about it.
Don't forget to prepare a data table.
Utilize the factor label method in all of your calculations.
Summing
Up:
1.
How many drops of water are in 2 L?
2.
How many drops of water are in Lake Erie?
3.
How many molecules of water are in Lake Erie?
4.
How many moles of water are in Lake Erie?
5.The
recommended daily allowance of water is about 2 L. How many molecules of water should you drink each day?
Activity 5
Teacher Notes
Mole
Competition
Concept
Development
Lab
Time: 1 class period
Teaching
Strategies:
Group the class so the students with the most ability to solve these
types of problems are distributed among the groups and continue to group
accordingly. Each member is to
have a job in the group. Each
group has a team name that they call out when they bring an answer up.
Points are awarded according to the order completed and whether the
answer is correct. (See attachment)
Activity 6
Teacher Notes
Do
You Catch Your Clippings?
Application
Lab
Time: 1 period
Objective:
In this activity, students will use a process similar to that used in
the Millikan oil drop experiment to find the ass of a single electron.
They will use this process to find the mass of a single paper clip from
the masses of groups of paper clips.
Teaching
Strategies:
The purpose of this activity is to have students find the mass of a
single paper clip without directly massing it.
It should be stressed before the students begin that they should never
mass a single paper clip, even after having completed all the measurements.
They also should never count the number of clips in or out of the
beaker at any time for the same reasons.
The students can only use their 25 massings to find the answer.
Jumbo paper clips are desirable, since any variation in mass is a small
percentage of the total mass of clips. A
digital scale is also desirable since the number of measurements needed is
considerable.
As the students are massing and looking for patterns, remind them of
Millikan's work with the oil drop experiment.
When students are looking at their data for patterns, ask if there may
be a better way of organizing their data.
When the results have been found, have the students report their
results to the class. Does the
mass of one paper clip seem to work with all of their data?
For example, if the mass of one paper clip is thought to be 1.5g, are
all the massings in the data table multiples of 1.5 g.
Summing
Up:
1.
Be sure the students explain their reasoning for their answers.
2.
Would more data have been better?
Answers will vary, but
more massing would only verify the common factor found.
3.
Interpretations
of individual sets of data will vary. Discrepancies
could result if not all paper clips were of uniform mass or due to massing
errors by the students.
Student Lab Sheet:
Do
You Catch Your Clippings?
Problem:
Can you determine the mass of a single paper clip without directly
massing it?
Procedure:
The purpose of this experiment is to simulate the experiment Millikan
used to determine the charge of one electron.
You are being asked to modify his procedures to determine the mass of
just one paper clip without directly measuring it.
The following ground rules must be followed:
1.
Masses may only be taken of the container holding an unknown number of
paper clips.
2.
You are to either remove or add a bunch of clips before each massing.
Never add or remove less than five clips.
3.
As you remove or replace clips; the total mass of the remaining clips
is to be recorded. The number of
clips removed and the number of clips remaining MAY NOT be determined by
counting. At least 25 mass
measurements are recommended.
4.
Form
a group plan to use your data to calculate the mass of one paper clip.
Summing
Up:
1.
Explain why your answer represents the mass of only one clip.
2.
How would additional massings affect the outcome?
3.
How
would you explain any observed discrepancies in your data?
Activity 7
Teacher Notes
Isotopic
Pennies
Application
Lab
Time: 1 period
Objective:
Students will apply what they have learned about weighted averages and
isotopes to a new situation - coins in a sealed container.
Teaching
Strategies:
You must mass a number of empty canisters for your students since they
should not open their containers. If
the containers are of a uniform mass, simply leave several empty containers
around for students to mass themselves.
Do not give students hints for this lab.
They should be able to figure out for themselves that they need to mass
an empty container.
You may wish to randomly place 15 pennies into each container, or you
may wish to predetermine the number of pre-1982 and post-1983 pennies placed
in each container. It will be
best to make sure that the containers are not all the same.
Some students may struggle with the mass, but resist the urge to give
them hints. Encourage them to go
back and look at previous work.
Summing
Up:
1.
Some students may solve this problem algebraically.
Other students may simply start with varying combinations of the two
types of pennies and adjust these combinations until the total calculated mass
equals their experimental value.
2.
Students
should realize that they must calculate a weighted average mass, just like
what must be done with isotopes to find average atomic mass.
Isotopes of the same element are alike except for the number of
neutrons. As a result, isotopes
of the same element have different masses.
In the same way, the fifteen objects students measured were all
pennies, but some of them differed in mass, just like isotopes.
Student Lab Sheet
Isotopic
Pennies
Problem:
How many pre-1982 and post-1983 pennies are contained within the film
canister?
Procedure:
According to Dalton's atomic hypothesis, all atoms of the same element
are identical. This notion of the
atoms, however, is somewhat outdated, as not all atoms of the same element
possess the same number of neutrons (possess a different atomic mass).
It is in this spirit, a demonic form of torture, involving pennies, has
been selected for you.
Starting in 1983, pennies were no longer made of pure copper, as the
cost of making a penny was becoming prohibitive.
Because of this, zinc, a much cheaper metal, was used in conjunction
with copper to make a penny. As a result, the newer pennies possess a different mass.
The task of this lab is to have you determine the number of pre-1982
and post-1983 pennies that are contained within a film canister without
opening it. In order to do this,
a couple of assumptions will be required.
First, there are 15 pennies in each container.
Second, the average mass of a pre-1982 penny is 3.10 grams and of a
post-1983 is 2.51 grams. Use what you already know about how average an atomic mass
was calculated for isotopes!
Summing
Up:
1.
Explain the process you used to determine the number of each type of
penny. Include your calculations
in your explanation.
2.
Explain how this lab relates to what has been discussed about isotopes.
Activity 8
Teacher Notes
Mole
Stations
Application
Lab
Time: 1 period
Teaching
Strategies:
Set up twelve stations at different locations around the lab.
At each station place containers that contain different masses.
Put anything in the containers to represent different masses of
elements. Pennies are a very
inexpensive source for the mass. The
students should not open or look inside the containers.
The station with the water could be a clear container so they can see
the water. The station that
represents ozone should be empty and record a mass for the container just
slightly lower than its actual mass so the students will get a result when
measuring for a very small amount of substance in the container.
Even though the students have not talked about compounds at this time
they should be able to figure out that ozone has three atoms for every mole of
the molecule.
Give different information on a note card and ask for unknowns.
The information may include:
Mass & element
# of moles
# Moles & element
mass
Mass & # moles
molar mass
Mass & # moles
element
# Atoms & element
mass
Set a timer so that each student spends 3 minutes at a
station to make the necessary measurements they feel they need to calculate
the unknown quantity. The teacher
can give the container mass or have empty containers to subtract it from the
total measured mass. Small film
canisters work well for this activity. Be careful, however, since all film
canisters do not have the same mass. (See attachment for sample problems)
Student Sheet
Mole
Stations
Purpose:
The purpose of this activity is to calculate moles, grams, molar mass,
or number of particles by making measurements of a given material.
Procedure:
1.
There is a series of lab stations arranged around the room.
By each lab station there is a note card with information on it.
Follow the directions and determine the unknown.
2.
You
will have three minutes to make all necessary measurements.
If you are done in less time use the time to do your calculations.
Do not move on to the next station until your teacher instructs you to.
Summing
Up:
1.
Make a data table and place all necessary information in it including
your measurements and calculations.
Activity 9
Teacher Notes
Unit
Test
Chalk
Talk
Objective:
By completing this activity students will be able to determine the
number of molecules (formula units) of chalk required to write their name.
Teaching
Strategies:
If students are not sure how to approach this problem, encourage them
to think about the exploratory activity in which they counted objects
indirectly. This should get them
started on the right track.
Summing
Up:
1.
To
determine the number of molecules in your name, first weigh a piece of chalk.
Write your name on the blackboard and then reweigh the chalk.
The difference in the masses is the mass of chalk required to write
your name. The number of
molecules can then be calculated.
2.
Data
table
3. As can be seen in the
calculations, by canceling out units, the number of molecules of chalk can be
determined. The conversion factor
of the number of molecules in one mole is needed to provide the link between
the mass of chalk and the number of molecules in one mole of chalk.
Student Test:
Problem:
How can you determine the number of molecules (formula units) of chalk
required to write your name?
Procedure:
Obtain a piece of chalk from your instructor.
Assuming that the composition of the chalk is calcium carbonate
determine the number of molecules of chalk required to write your name on the
blackboard.
Summing
Up:
1.
Explain the procedure, which you will use in determining the number of
molecules of chalk required to write your name.
Be specific!
2.
Prepare a data table and record your data and calculations.
Be sure to include units on all of your numbers.
3.
Explain the logic of your calculations.
Be specific. Why was each step performed?
Is it necessary to know the number of molecules in 1 mole?
Inner
Space:
Students work with a partner. Teacher
is the facilitator. Answer with a
question. What do you think?
Rice-O-Rama:
Students work with a partner. Teacher
is the facilitator. Don’t lead the students.
They will really come up with solutions.
Just give them a chance. Don't
get tempted to tell them.
PowerPoint:
Students will take notes next to the printout of the slide.
Video:
Students will view the video and answer the questions as they watch.
When video is finished students will get together with a partner to
discuss questions.
Bean
Salad:
Students will work with a partner
Molecules
of Water in Lake Erie:
same as bean salad
Mole
Competition:
Students will work in a small group to answer a question.
Do
You Catch Your Clippings?
Students will work with a partner.
Isotopic
Pennies:
Work with a partner. Teacher
is the facilitator.
Mole
Stations:
Students will work independently to solve the lab problems. Teacher is
the facilitator.
Chalk
Talk Test:
This can be optional. It
could be a partner ability based test or done individually.
Inner
Space:
Exploration activities encourage students to observe relationships,
identify variables and develop tentative explanations of phenomenon.
Some students may be able to design experiments that will hopefully
lead to formulating models. The
questions that are raised and the methods proposed for investigating those
questions are the most vital parts of this initial stage.
Most exploration activities are at least slightly directive in the way
they lead students into a more complete understanding of the purpose of the
activity. Students that propose
incorrect conclusions should not be penalized, but instead be encouraged to
continue to search for explanations of the activities they observe.
The classroom atmosphere should ideally enhance curiosity and interest
and encourage both the aggressive and timid students to become equally
involved. Exploration activities
should be concluded before students' interest starts to subside - some might
span only 10-20 minutes. Student is graded on participation.
Rice-O-Rama:
Student is graded on participation.
This is an inquiry lab and is based on their creativity.
Bean
Salad:
Assessment is based on organization of data and calculations made with
the collected data
Molecules
of Water in Lake Erie:
Assessment is based on the organization of data in their table and
their utilization of the factor label method.
Mole
Competition:
This is a fun activity that gives them practice on solving mole
problems. Students work
cooperatively to reach a consensus.
Do
You Catch Your Clippings?
Assessment is based on the organization of collected data and the
solution reached for their mass of one paper clip.
Isotopic
Pennies:
Assessment is based on their problem solving skills to assess the
number of pre and post pennies in their container.
Mole
Stations:
Assessment is based on organization of the data and calculations.
Chalk
Talk Test:
Assessment is based on the thought process to how they calculated their
answer. Organization of the data
collected to the data collected.
Inner
Space:
no lab equipment necessary
Rice-O-Rama:
containers of small uniform objects, metric balance, ruler, graduated
cylinders, beakers, etc... If students want to try something they don't have
just have them check with the teacher first to make sure it isn't a safety
concern. If it isn't let them
try. Even if you know it won't
work, let them figure it out. It
may lead to another idea.
Bean
Salad:
Baggies, one-pound bags of dried kidney beans,
pinto
beans and black-eyed peas. Mix the three kinds of beans together by placing a
handful in each baggie. This will
make approximately 28 bags.
How
Many Molecules of Water Are in Lake Erie:
water, balance, eyedropper, beaker, and graduated cylinder.
Do
You Catch Your Clippings?
Box of jumbo paper clips per student group, beaker, decigram or
centigram balance
Isotopic
Pennies:
film canister of 15 pennies, metric balance, empty film canister
Mole
Stations:
samples of materials, balance
Chalk
Talk Test:
one piece of chalk, metric balance
Other
tools that are appropriate can be utilized.
For example the computer for lab reports, graphing calculators for
calculations, (the screen can also be printed and put in lab report.)
Overhead projector, etc…
These
activities in this unit are based on the learning cycle.
The exploration activities are at least slightly directive in the way
they lead students into a more complete understanding of the purpose of the
activity. Students that propose
incorrect conclusions should not be penalized, but instead be encouraged to
continue to search for explanations of the activities they observe.
The classroom atmosphere should ideally enhance curiosity and interest
and encourage both the aggressive and timid students to become equally
involved. Exploration activities
should be concluded before students' interest starts to subside - some might
span only 10-20 minutes.
Concept
development involves the development of the concept based on the experiences
in the exploration phase of the learning cycle.
Mental processes are provided through social interaction between
student and student or student and teacher.
The teacher, texts, computers, films and other media, may aid the
concept introduction. It is
closely related to traditional classroom instruction.
Audio-visuals, problem sets, assigned reading, individualized and group
instruction would all be common methods of helping the students to correctly
formalize the initial concepts from the exploration activity.
An
important component is that the common experiences, which occurred during the
exploration phase, are referred to in the concept development process.
In the application phase of the learning cycle, the student tests the
schemes or generalization, which seemed to bring observations and explanations
back into the whole picture. If
the concept can be generalized to apply in another somewhat different event,
the interpretation is assimilated into the concept previously developed or
reinforced for more meaningful learning.
The emphasis is not to discover or verify, but rather to use the
concept. The students analyze a phenomenon using the patterns or relationships
that were first formulated during the exploratory activity and clarified
during the concept development.
I
would like to give credit to most of these activities to the Iowa Chemistry
Task Force in conjunction with the University of Northern Iowa.