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From Molecules to Mole Day Do's
Mole Day Activities for Teachers to do with
Families |
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Prep for Teachers
Prior to the activity, bookmark each of the Web sites used in the lesson.
Load the Shockwave plug-in onto all computers in your classroom. CUE
the videotapes to their appropriate starting points. Prepare copies
of the handouts.
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Print out World of Chemistry Chemical Composition
Flash Cards. Make sufficient copies for the class, with one set of cards
per seven participants. If desired, mount the cards onto index cards using
glue or tape.
When using media, provide students with a FOCUS FOR MEDIA INTERACTION,
a specific task to complete and/or information to identify during or after
viewing video segments and Web sites.
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Step 1:
In this first activity, you will establish a context for understanding
standards in measurement. Break the class into groups with three or four
members, and give each group of learners a “Sci Island” activity
sheet. This activity sheet will allow participants to compare measurements
made using two different systems of measurement – the English system,
represented by the map of the United States, and the SI system, represented
by the tilted flask. It will also allow them to better understand the
benefits of a system that uses fewer base units over a system that uses
many units to measure the same quantity. Give each group about 3 minutes
to complete this activity. Initiate discussion concerning inherent problems
of measurement resulting from differences in units.
Initiate discussion by asking participants how many different units they
brainstormed to measure amount of matter in the United States. (Answers
should represent at least three of the following units: pounds, ounces,
cups, teaspoons, tablespoons, tons.) Continue by asking them how many
different units they brainstormed to measure distance. (Possible answers
may include mile, nautical mile, inch, foot, yard, and league.) Ask participants
to consider the same questions on Sci Island. Immediately they may identify
fewer options and most of the responses will have a common base unit.
(Gram, kilogram, milligram, meter, kilometer, centimeter.)
Introduce the term base 10 to participants as part of the discussion.
The base 10 system used by the International System (SI) connects base
units like the gram or the meter by a factor of 10 to the other units
discussed. Inherent problems to the English system of measurement include
the inconsistencies in units. For example, 12 inches equals 1 foot, 3
feet equals 1 yard, and 1 mile equals 1760 yards: none of the numbers
are related.
Ask students to discuss possible problems scientists encounter when trying
to standardize international units of measurement when compared to those
used in the United States. Explore with students the historical evolution
of the foot as a unit. If the "king's foot" was the standard,
then as one king died and was replaced, the unit also changed.
Invite several students to walk the same distance in the room and count
the number of "feet" or steps required to go the same distance.
Participants will begin to discern issues of the standard as well as the
ways in which measurements are made: one person's step is another person's
stride. Explain to learners that the mole is a unit developed in the 1700s
to address unit inconsistencies surrounding matter. Therefore standards
are quantities used to compare unknown values with known values.
Step 2:
Next, students will begin to appreciate the utility of scientific notation.
Ask learners to mentally calculate the following progression of numbers.
Problems
A. 2 x 4
B. 2.5 x 42
C. .25 x 42
D. .0025 x .042
E. 250 x 42
F. 2500 x 4200
G. 2500000000 x 4200000
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Answers
8
105
10.5
0.000105
10500
10500000
10500000000000000
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It is clear to see how quickly the calculations become unwieldy. List
the answers on the board. It is also clear to see that each of the resulting
numbers from B through G has the same basic structure. The second calculation
is best performed using the distributive property – 42(2 + 0.5) –
by multiplying 42 by 2 (84) then adding the product 42 x 0.5(21) ==>
84 + 21 = 105. Calculations that precede B are based on its result; multiplying
(or dividing) by a factor of ten will result in the movement of the decimal
point to the right or the left respectively.
Distribute the “Scientific Notation” worksheet to each group.
Explain to learners that scientific notation is a base 10 system that
allows for facile calculations of very large numbers. Remind participants
that the base 10 system was discussed earlier and is used to connect units
in the International System (SI) of measurement. Instruct participants
to go to the Discovery School Webmath site at http://school.discovery.com/homeworkhelp/webmath/sn_convert.html.
Ask students to identify clues that demonstrate that scientific notation
is a base 10 system from the yellow box on the Web page. (Participants
will notice that for the interactive component "Convert numbers to
scientific notation," a space is provided for input followed by a
non-interactive "x 10" followed by another data field. Because
all input will have to be multiplied by 10, all results are based on or
are changed by a factor of 10.)
Provide students with a FOCUS FOR MEDIA INTERACTION, asking participants
to review the Discovery School Webmath site and identify the mass
of Earth in kilograms. Ask students to indicate when they have found the
answer by raising their hands. While students are searching, write the
following "astronomical" measurements on the board: the mass
of the Earth (59800000000000000000000 kg); the orbit distance of Earth
to the sun (149,600,000 km); diameter of Earth (12756.3 km). Instruct
groups to use the Discovery School Site to convert Earth's orbit and diameter
to scientific notation. Record responses on the “Scientific Notation”
worksheet under real life context.
Instruct groups to complete the Scientific notation worksheet using the
previously bookmarked NYU site http://www.nyu.edu/pages/mathmol/textbook/scinot.html.
Step 1:
FAST FORWARD Mole Concept #4 to the point at which "AVOGADRO'S
HYPOTHESIS" appears on a black screen and you hear music. Provide
students with a FOCUS FOR MEDIA INTERACTION by asking them to identify
and record Avogadro's Hypothesis. PLAY tape. PAUSE tape
when narrator states, "Each volume contains at least two atoms called
molecules."
CHECK for understanding by asking students what Avogadro's Hypothesis
is. (Avogadro's Hypothesis states that equal volumes of gas at the same
temperature and pressure contain equal numbers of particles.) CHECK
for further understanding by asking students to state the differences
between atoms, ions, and molecules. (Atoms are small particles
of matter. Ions are charged particles/atoms that gain their charge
because of the loss or gain of electrons. Molecules are "systems"
of atoms that are bonded together to form a unit of matter.)
Step 2:
Insert Mole Concept #6 into your VCR. FAST FORWARD to the
point at which you see the image of a scale. The narrator states, "Ideally,
we'd like to use a balanced scale to compare masses. Provide learners
with a FOCUS FOR MEDIA INTERACTION, asking students to watch for
changes in numerical values associated with nitrogen and oxygen from 28
and 32 to 14 and 16, respectively. Ask students to speculate why there
was a change and what these numbers represent when compared to a periodic
table. PLAY the tape. PAUSE the tape when the narrator states,
"We have a practical tool for comparing atoms," and you see
a close-up of a red sphere representing oxygen changing to a red cube
on the screen. CHECK for student understanding by asking students
why the change occurred. (Both nitrogen and oxygen are naturally diatomic.
The mass of each atom is indicated by the second set of numbers whereas
the first values indicate the masses of the diatomic molecules.)
Lead a discussion about the nature of gases when compared to solids and
liquids. The three most common states of matter are solids, liquids, and
gases. Each may be defined by the distance between particles and the energy
associated with the particles. The particles of a solid are relatively
close to each other and moving very slowly, whereas those of a gas are
very far apart and moving rather quickly; the particles of a liquid are
intermediate between the latter and the former. Ask students if they think
gases like nitrogen and oxygen can be measured like solids or liquids.
Engage discussion in challenges to their comparison. (Possible challenges
include the ability to contain substances that were so different. Gases
by definition have no definite shape so the ability to measure gases is
reduced when compared to solids and liquids.) Provide students with a
FOCUS FOR MEDIA INTERACTION, asking students to speculate how small
or large a number would be required to standardize all of the different
types of matter. PLAY tape. PAUSE tape when image of an
the words "PICK A NUMBER" appear on the screen in small caps,
and the narrator states, "If we always pick the same number of atoms,
we always have the same number of atoms." CHECK for comprehension.
(Discussion should suggest that the standard that allows for comparison
of gases is probably very large. Introduce the notion that a mole is much
like a dozen and has a specific number associated with it. While a dozen
eggs represent 12 eggs and a dozen chickens represent 12 chickens, the
mass of 12 eggs is significantly less than that of 12 chickens.)
FAST FORWARD tape to the image of a black "lump" on a
scale. The narrator states, "What we need is a more useful number."
Provide students with a FOCUS FOR MEDIA INTERACTION, asking them
to determine the name of the special number scientists use to compare
atoms and which element this number is based on. Additionally, ask them
to raise their hand when they can identify the meaning of relative atomic
mass. PLAY tape. STOP when you see students raise their
hands. CHECK for student understanding. Ask students what that
special number is. (The name of the number is Avogadro's Number and it
was determined based on work done with Carbon-12.) Ask students what relative
atomic mass is. (The relative atomic mass allows for the comparison of
different atoms in the form of ratios based on data presented in the periodic
table.) Observe that hydrogen has a relative mass of 1g, sodium has a
relative mass of 23g, calcium has a mass of 40g, and sulfur has a mass
of 32g.
CUE tape to where you see a horizontal display for hydrogen, carbon,
sodium, sulfur, and calcium. Provide students with a FOCUS FOR MEDIA
INTERACTION by asking them to calculate the relative atomic mass (molecular
mass) of iron II sulfide (1 atom of iron + 1 atom of sulfur) and explain
the statement "the mole is the universal standard container."
PLAY tape. PAUSE tape once the molecular mass of iron II
sulfide is determined on screen. (Iron II sulfide has a molecular mass
of 87.9g. The mole allows one to measure in grams an amount of a substance
based on the relative atomic mass displayed on the periodic table.)
FAST FORWARD tape to a yellow screen with the words "AVOGADRO'S
NUMBER" in small caps. The narrator asks, "Are you curious about
Avogadro's number?" MUTE volume. Provide students with a FOCUS
FOR MEDIA INTERACTION, asking students to write Avogadro's Number
in scientific notation. PAUSE tape when three columns of numbers
appear on the screen. Allow students time to write Avogadro's Number in
scientific notation. (6.02 x 1023) Resume normal volume. Provide students
with a FOCUS FOR MEDIA INTERACTION, asking them to identify three
ways a mole is calculated. PLAY remainder of episode. (The mole
is defined using the atomic/molecular mass, 22.4 L of gas at standard
temperature and pressure or as 6.02 x 1023 particles.)
Step 3:
CHECK for understanding using concept mapping. Distribute newsprint
to each group. Instruct each group to write the word MOLE in capital
letters in the center of a piece of newsprint. Instruct groups to treat
the term MOLE as a tree and develop branches of related ideas germane
to the activities presented in the lesson and/or list applications of
the MOLE to other ideas. Create a concept map of ideas around the
mole on newsprint. A sample concept map is provided at the end of the
lesson. Display the work of each group around the room, exhibit style.
Allow groups to promenade around the room to make sure each group has
understands key concepts.
Step 1:
Review vocabulary related to the concept of the mole, and introduce ideas
useful to scientists when determining chemical properties of substances.
Break the class into working groups of 7-member teams. Distribute the
Houghton Mifflin Flash Cards to each group. These flash cards are available
online at http://college.hmco.com/chemistry/general/zumdahl/world_of_chem/1e/students/flashcards/ch06
/index.html. Allow the class 2-3 minutes to study their cards. Allow
the group 5-7 minutes to review all of the vocabulary represented on the
flash cards. Instruct each student to record vocabulary in their own notebook.
Step 2:
As a fun evaluation, engage the teams in friendly competition. There are
three major ideas presented in this lesson:
- The mole as a standard unit of measurement
- The utility of scientific notation when working with numbers in
science
- Conversion of measurements related to the mole, atomic mass, and
physical mass
These three major ideas are used to form strands of players, sub-teams
within a larger team. Each team must designate a leader and strand experts
in four categories. The four strand categories are:
- Scientific notation
- Mass Mole Calculation
- Mole-Particle Calculation
- Arcade
The strands are designated so that team members can pair up to complete
each challenge. This is also a differentiated evaluation. Younger participants,
or those who are not agile at complex calculations, can organize and record
scores, serve as "calculator" experts, or participate in the
arcade-style "Whack-a-Mole" competition. Create review teams
by combining at least two groups. Distribute “Round-Robin Rules”
sheets. Set a 5-minute time limit to review competition rules. Allow teams
to huddle to create strands within each team. Each strand should have
2-3 members.
Create review stations while teams create strands by opening and minimizing
the four Web pages used for this activity:
Addison
Wesley Scientific Notation quiz
http://www.mccc.edu/~kelld/scientific/scientific.htm
Glencoe
online Chapter 11 Mole Science Quiz
http://glencoe.com/qe/science.php?qi=978
Visionlearning
Mole Quiz
http://www.visionlearning.com/library/science/chemistry-1/CHE1.5-t-mole.htm
Whack-a-Mole
game
http://www.alfy.com/Arcade/Shockwave/Mole/index.asp
Cover each of the screens with an opaque piece of construction paper taped
to the top of the monitor so that the contents of the page are not visible
to any of the teams. Once strands are formed, instruct the scientific
notation review strand to take their position in front of one of the review
stations. Give each team seven minutes to complete as many questions on
each of the 3 review sites. Assure teams that they may not be able to
complete all of the questions in the allotted time frame. The fourth site
is an arcade-style game. Allow three players to earn points by allowing
one player at each level of play. In total, the competition will take
about thirty minutes.
ART
Engage learners in an art contest to create a Mole Day logo. Visit the
National Mole Day Foundation, Inc. Web site at http://www.moleday.org
to generate discussion and gather ideas.
MATH
Mole data also provides important empirical data about the composition
of substances. Understanding ways that percentages are used by scientists
is a critical skill. Gather samples of household items that list percent
data (examples: 50% isopropyl alcohol, 3% hydrogen peroxide, 5% bleach
sodium hypochlorite). Assuming the only other major component of the solution
is water, calculate how much water is in each solution. The molecular
formula allows scientists to calculate how many moles of each atom are
in a molecule of a substance. The molecular formulae are, C3H8O, H2O2,
and NaOCl respectively for the household items listed above. The subscripts
indicate the number of moles of each atom per molecule of the substance.
Using the molecular formulae and a periodic table, calculate the molecular
mass of each substance by adding individual atomic masses, then calculate
the percentage of each atom in each molecule by mass. I like to call this
the PMS method for calculating the empirical formula because when
based on a 100g sample, the Percent data can be converted to Moles
using atomic masses in order to Solve for the formula.
Substance
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% Water
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Molecular Mass
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% Composition by Mass
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Isopropyl alcohol,
C3H8O |
50 |
60 amu |
C: 60%
H: 13.3%
O: 26.7% |
Hydrogen peroxide,
H2O2 |
97 |
34 amu |
H: 6%
O: 94% |
Sodium hypochlorite (bleach),
NaOCl |
95 |
74.5 amu |
Na: 31%
O: 21%
Cl: 48% |
- Mole Day is an opportunity early in the academic year to allow families
to learn along with their students about a key concept in the study
of chemistry. Visit the FANS Project Web site at http://dimacs.rutgers.edu/fans/
to gather ideas about how families can achieve standards in math and
science education.
- Invite a local university student group to perform demonstrations
or serve as mentors in career activities
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- The American Chemical Society often has student chapters who enjoy
visiting high schools. Visit the society online at http://www.acs.org/portal/Chemistry?PID=acsdisplay.html&DOC=education%5C
student%5Cstudaffs.html.
- Many colleges now also require community service. As the nation
embraces "No Child Left Behind" legislation, the creation
of family involvement activities is a great way to build alliances
with families, students, teachers, and schools.
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