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UP AND ATOM
SCIENCE
PATSY PARTIN AND ELANA JONES
Overview
The periodic table is one of the most
important tools of a scientist because
it is a classification system used to
organize vast amounts of information
in a logical, useable, and meaningful
way. Much information can be
gathered about an element from its
position in the periodic table; one
can predict physical and chemical
properties of a particular element
and one can predict what other
elements a specific element will react
with chemically.
Four important facts about an
element are given in each square of
the Periodic table: atomic number,
atomic mass, chemical symbol and
name. The number of protons in an
element determines its properties.
The number at the top of each
square in the table tells how many
protons the element has; the atomic
number is unique to that element;
no two elements have the same
atomic number. Below the atomic
number in the center of the square is
the chemical symbol for the element.
Below the chemical symbol, the
name of the element is spelled out.
The number near the bottom of the
square is the atomic mass of the
element. The atomic mass is made
up of the protons and neutrons in
each atom.
In this lesson, students will explore
the most basic particles by
GRADES 7-8
examining their chemical make up
and reaction to other particles. They
will use the Periodic Table, Internet,
video and lab experiences to work
with and identify various elements
and their properties.
ITV Series
Eureka #122 “Atoms”
Eureka #123 “Electrons”
Learning Objectives
Students will be able to:
• Compare the four states of
matter and describe the events
that take place during a change
of state.
• Distinguish between physical and
chemical changes.
• Identify the three types of
particles found in an atom.
• Compare and contrast mass
number and atomic mass.
• Plan, create, edit, and format a
spreadsheet on subatomic
particles.
• Sketch the electron arrangement
of an atom, given its atomic
number.
• Calculate the number of neutrons
in an atom based upon the mass
number and number of protons
for 40 different elements on the
spreadsheet.
• Construct atomic model drawings
and use them to make a Periodic
Table.
• Use the Periodic Table to identify
properties of specific elements.
UP AND ATOM
SCIENCE
PATSY PARTIN AND ELANA JONES
GRADES 7-8
•
Scissors
String
Ruler
•
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•
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Distinguish between periods and
groups of elements in the
Periodic Table.
Compare and contrast the
elements in a family of the
periodic table.
Sequence the elements of the
periodic table by family and
period.
Compare and identify elements,
compounds, and mixtures.
Develop and apply skills in
predicting, information gathering,
and charting.
Develop and apply skills in
mathematical calculations,
summarizing and recording
information.
Develop and apply skills in critical
analysis of results.
Vocabulary
Atom
Nucleus
Electron
Neutron
Proton
Atomic number
Mass number
Periodic law
Compound
Chemical formula
Chemical bond
Materials
Per Student:
1 Pencil
1 Thin spiral notebook
Colored pencils or markers
LAB #1 Per Student
Periodic Table
Unlined paper
Pencil
Metric ruler
Drawing compass (optional)
LAB #2 Per Student
Periodic Table
Unlined paper
Drawing compass (optional)
Metric ruler
Pencil
Per Class
Posterboard
Per Group
Scissors
Tape
Lab #3 Per Student
Samples of elements (Al, Cu, Fe, C,
S, I, Sn, Pb, and Zn)
Hydrochloric acid
Small hammer
Chisel or nail
Conductivity apparatus
Beaker
5 test tubes
Dropper
Goggles
Apron
Lab worksheet or Lab Journal
Pencil
UP AND ATOM
SCIENCE
GRADES 7-8
PATSY PARTIN AND ELANA JONES
Pre-Viewing Activities
uncharged atom has the same
number of electrons as protons.”
www.shef.ac.uk/~chem/web-elements/
To check for comprehension, ask
students the number of electrons in
the nucleus of an atom in 10-15
elements.
Bookmark the following Internet
sites prior to class:
Interactive Periodic Table
Periodic Tables
www.yahoo.com/science/chemistry/
Periodic_Table_of_the_Elements
Take students to one of the sites
above and demonstrate how to
determine the number of protons,
neutrons, and electrons in an atom
from the Periodic Table.
Draw a key to the Periodic Table on
the whiteboard with dry erase
markers or have transparency ready
to put on an overhead projector.
Example:
6_____________atomic number
C ____________symbol of element
Carbon __________name of element
12 ____________mass number
SAY, “The atomic number is the
number of protons in the nucleus of
the atom.” Call on students to find
the atomic number (and number of
protons) for 10 –15 elements. Using
informal “oral testing” make sure
that every student understands how
to determine the number of protons;
students may be paired with a peer
for a cooperative learning variation.
(ESL students and mainstreamed
special education students might find
peer tutoring especially helpful for
this study.) Next SAY, “An
SAY, “The mass number is the total
of the protons and neutrons in an
atom.” Write an example of a mass
number on the whiteboard.
Beryllium
4 protons + 5neutrons
9 = mass number (atomic mass unit)
Write a chart describing the three
particles in an atom on the
whiteboard or have a transparency
of this chart prepared to use on the
overhead projector.
Chart:
PARTICLE
Proton
Neutron
Electron
RELATIVE MASS CHARGE LOCATION
1
1
0
1+
0
1-
Nucleus
Nucleus
Outside
Nucleus
(orbiting in
energy levels)
SAY, “ Notice that protons and
neutrons have the same mass. All
the mass of an atom is in the
nucleus since protons and neutrons
are the biggest particles and are
located in the nucleus. The
electrons have very little mass
UP AND ATOM
SCIENCE
PATSY PARTIN AND ELANA JONES
(actually it is 1/1836) so we consider
the mass of an electron to be 0.
As you can see the proton and the
electron have opposite charges. The
proton is a positively charged particle
in the nucleus of the atom. The
electron is a negatively charged
particle that circles outside the
nucleus in paths called energy
circles. The neutron, also located in
the nucleus, is a particle with no
charge”.
Write the formula on the whiteboard
for finding out the number of
neutrons in an atom or have a
transparency prepared to go on the
overhead projector.
Remind students:
1)
Atomic number = number
of protons in atom
2)
Same number of electrons
as protons
Formula to find number of neutrons
in an atom:
mass number - atomic number =
number of neutrons
Pose the Questions: “What are the
particles that make up matter? Are
these particles the same in all kinds
of matter?”
Focus for Viewing
To give students a specific
responsibility while viewing say,
GRADES 7-8
“Watch the video and compare your
answers with the answers featured
in the video. You specifically want to
know what the smallest particles are
and if they are the same in all forms
of matter.”
Viewing Activities
Eureka #122 “Atoms”
FAST FORWARD video and be
ready to begin immediately following
introductory segment . Audio is “Our
story begins with atoms.” Visual is
cartoon bird narrator with cartoon
tree. To give students a specific
responsibility while viewing ASK,
“How are atoms of pure elements
different from the molecules in nonmetals, liquids, and gases? As you
watch the video, discover if pure
elements have molecules or atoms.”
BEGIN video.
STOP the video at the visual of the
cartoon narrator made of Legos and
the audio is “Be thankful you don’t
live in a world of Lego.” Allow
students to list examples of pure
elements such as gold, lead, silver,
aluminum, copper, and iron. Allow
time to discuss atomic characteristics
in pure elements. Allow adequate
time for interactive class discussion.
SAY, “What characteristics did you
observe in the video for pure
elements?” Allow students to
compare observations made of
UP AND ATOM
SCIENCE
PATSY PARTIN AND ELANA JONES
characteristics. Discuss the rationale
for each answer. SAY, “Imagine
taking a pure sample of an element,
such as gold, and cutting it in half.
Suppose you cut it in half again and
again. You would finally have a
piece so tiny that it could not be
divided further and still be gold.
That piece is called an atom. An
atom is the smallest particle of an
element that has the properties of
that element. What is a model of
something?” (A means by which
scientists try to explain something
they cannot see or understand by
relating it to something that they do
see or understand.) Accept all
reasonable responses.
SAY, “Democritus, a Greek
philosopher who lived over 2000
years ago, was the first person to
form a model of the atom. His
model suggested that all matter has
made up of small, indivisible articles.
The model of the atom has
undergone many modifications since
John Dalton proposed a model of an
atom in 1803. Dalton’s model
depicted the atom as a solid,
indivisible sphere. In 1897, J.J.
Thomson, a British physicist, showed
that atoms contained negatively
charged particles that he called
electrons. Thomson’s model of the
atom showed a positively charged
sphere with electrons embedded in
it.
GRADES 7-8
In 1911, Ernest Rutherford’s famous
gold foil experiment led to the
discovery that the atom consisted of
a tiny, densely packed, positively
charged core, or nucleus, with
electrons orbiting the nucleus at
some distance. Most of the atom
consisted of “empty” space.
In 1932, James Chadwick, one of
Rutherford’s students, found
evidence of the neutron, the
existence of which had been
predicted by Rutherford.”
Show a picture of an atom and SAY,
“It is difficult to really imagine the
size of an atom. The period at the
end of this sentence might hold one
hundred billion atoms! What particles
make up an atom?” Allow students
to discuss. Accept all reasonable
responses. ASK, “Can you compare
the sizes of the parts of an atom?”
Allow students to discuss. Accept all
reasonable responses.
SAY, “Imagine an atom is the size of
a large football stadium. Its nucleus
would have the volume of a small
marble in the center of the field.
The electrons would be like tiny
insects buzzing around in the
stands.” Encourage discussion
among the students. Accept all
reasonable responses.
UP AND ATOM
SCIENCE
PATSY PARTIN AND ELANA JONES
Eureka #123 “Electrons”
To give students a specific
responsibility while viewing ASK,
“What are the three types of
particles found in an atom? How are
they alike and how are they
different?
Let’s see if you were right.”
Students will validate their answers
as they watch the video.
FAST FORWARD and be ready to
begin immediately following the
opening segment. Audio is “The
story so far ---all substances in all
three states of matter are made up
of little round things called atoms.”
Visual is the same words written on
screen. BEGIN video.
PAUSE the video after each type of
particle is highlighted. Use a dry
erase marker to outline each type of
particle on the television monitor as
a further validation point. RESUME
video after each point is validated.
SAY, “What is the name scientists
give to the kernel of the atom?” Use
a dry erase marker to outline the
word as a further validation point.
SAY, “How do atoms give the
illusion of being solid spheres?”
Students will validate their answers
as they view each segment of the
video.
STOP the tape as the narrator says,
“So what are you complaining
GRADES 7-8
about?” Visually, a narrator is
running into a lamppost. SAY,
“Rutherford calculated that the
diameter of the atom is more than
100,000 times that of the nucleus.
So an atom is mostly empty space!”
Invite students to draw each particle
in an atom using the Bohr model of
the atom. How can we draw
electrons around the nucleus?”
Allow time for students to respond
and to compare their anticipated
responses.
SAY, “According to this model,
electrons move in paths called
energy levels. Think of the energy
levels as rings around the nucleus.
The energy levels, or rings are
always referred to by numbers.
Level I is the level closest to the
nucleus. Each energy level of an
atom can hold a certain number of
electrons.”
SAY, “The first energy level can hold
up to 2 electrons. The second
energy level can hold up to 8
electrons. The third energy level can
hold up to 18 electrons, and the
fourth can hold up to 32 electrons.
The term ‘shell’ is often used when
referring to an energy level.”
Encourage students to study the
diagram of the first four energy
levels of an atom. Guide discussion
as students brainstorm and respond.
UP AND ATOM
SCIENCE
GRADES 7-8
PATSY PARTIN AND ELANA JONES
Draw a diagram (or have a prepared
transparency) of the first four energy
levels of an atom showing the
different numbers of electrons each
holds.
SAY, “The electrons that have the
most effect on the properties of an
element are those found in the outer
energy level. The outer energy level
is the one farthest from the nucleus.
SAY, “All electrons are the same.
They have the same mass and
charge, but there is significance in
the number of electrons and the way
in which they are arranged in an
atom.”
Atoms - Lab #1
Activity: “Drawing Models of Atoms”
Materials (per student)
Periodic Table
Unlined paper
Pencil
Metric ruler
Drawing compass (optional)
SAY, “This activity introduces a
diagram as a model for the atom.
This model is only a representation
and is not three-dimensional.”
Before attempting this activity,
review with the students how to
determine the number of protons,
neutrons, and electrons in an atom.
Allow special needs students to work
with a peer, if necessary.
Procedure
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Use the Periodic Table, from the
book, or from the Internet to find
the number of protons, neutrons,
and electrons in an atom in the
first element of the Periodic
Table. Calculate to determine
number of neutrons in the atom.
On a piece of unlined paper draw
a circle 1 cm in diameter. This
small circle stands for the
nucleus.
Write the number of protons in
the circle next to a positive (+)
sign. The P+ stands for protons.
Write the number of neutrons in
the circle next to the letter n. The
N stands for neutrons.
Show the correct number of
electrons in each atom by placing
them in the proper energy levels.
Make the first energy level a
dashed circle 3.0 cm in diameter.
The circles around the nucleus
show the energy levels. The estands for electrons.
If needed make the second
energy level a dashed circle 5.0
cm in diameter; make the third
energy level a dashed circle 6.0
cm in diameter; make the fourth
energy level a dashed circle 7.0
cm in diameter. On the correct
circles write the number of
electrons next to a negative (-)
sign.
UP AND ATOM
SCIENCE
GRADES 7-8
PATSY PARTIN AND ELANA JONES
•
Using the steps above, repeat for
the first 40 elements listed in the
Periodic Table. This activity will
take two class periods for
optimum understanding. This
activity can be extended to
include more atoms until you feel
students can draw a model of any
given atom.
Atoms - Lab #2
Activity: “How is the Periodic Table
Arranged?”
Materials (per student)
Periodic Table
Unlined paper
Drawing compass (optional)
Metric ruler
Pencil
Posterboard (per class)
Scissors (per group of students)
Tape (per group of students)
SAY, “The objective for this activity
is to construct atomic model
drawings and use them to make an
example of a Periodic Table with
only18 elements. Remember the
current Periodic Table has 109
elements!”
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Procedure
•
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A group of students will measure
and cut out eighteen 8-cm
squares of unlined paper (six
students per group)
On each square of paper,
students will make a drawing to
•
serve as a model of an atom for
the first 18 elements listed in the
Periodic Table. Have the
transparency on the overhead
projector to serve as a model for
students to follow. The teacher
also should draw some models of
atoms for specific elements on
whiteboard to get students
started.
For each model, use a circle 1.0
cm in diameter as a nucleus.
Use the atomic number and the
mass number to determine the
number of protons and neutrons
in the nucleus of each atom.
Indicate these numbers on each
drawing.
Show the correct number of
electrons in each atom by placing
them in the proper energy levels.
Make the first energy level a
dashed circle 3.0 cm in diameter.
Make the second energy level a
dashed circle 5.0 cm in diameter.
Make the third energy level a
dashed circle 6.0 cm in diameter.
Arrange the models in order of
increasing atomic number on
student desk or lab table.
Look at the drawings and arrange
them in a table so that each
column contains atoms with
similar features. Mount the
squares in this arrangement on
posterboard.
Have students answer these
questions using their Periodic
Table. (Using these results to
UP AND ATOM
SCIENCE
PATSY PARTIN AND ELANA JONES
draw conclusions will sharpen
their critical thinking skills.)
a)
b)
c)
How many groups does your
Periodic Table have? (should
have 8 groups)
How many periods does your
Periodic Table have? (should
have 3 periods)
Where would you place an
with an atomic number of 19
and a mass number of39?
Explain the answer. (An atom
with atomic number 19 would
be placed below the atom
with atomic number 11 in the
fourth period because they
both have one electron in
their outermost energy
levels.)
Atoms – Lab #3
Activity: “What Are Some Properties
of Metals and Nonmetals?”
Materials (per student)
Samples of elements (Al, Cu, Fe, C,
S, I, Sn, Pb, and Zn)
Hydrochloric acid
Small hammer
Chisel or nail
Conductivity apparatus
Beaker
5 test tubes
Dropper
Goggles
Apron
Lab worksheet or Lab Journal
Pencil
GRADES 7-8
SAY, “This activity will give students
an opportunity to explore some
properties of metals and nonmetals.”
Ask students to group the materials
in broad categories. Use many
different samples of metals and
nonmetals. Provide labeled samples
of the elements listed.
Providing chemical handbooks for
students to use to determine
physical properties would be
advantageous.
Students should observe each
sample and describe the physical
properties they would use to identify
the elements.
CAUTION: Remind students not to
taste or touch the elements. Do
not use any Group I metals because
they are highly reactive.
Since none of the material listed will
react with HCL perhaps you could
demonstrate the reaction with
magnesium. Avoid hammering
magnesium. Stress proper
laboratory procedures in using iodine
and hydrochloric acid.
Procedure
Wear goggles and an apron. Do not
touch iodine crystals. Handle
hydrochloric acid carefully. If
spillage occurs, rinse area with
plenty of water.
UP AND ATOM
SCIENCE
GRADES 7-8
PATSY PARTIN AND ELANA JONES
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Obtain a small sample of each
element. Observe the physical
properties that are apparent.
Record your observations for
each sample in lab journal or
worksheet.
With the small hammer, try to
drive the chisel or nail into the
sample. This procedure tests the
“malleability” of the sample.
Record the observations.
Using the conductivity apparatus,
touch the two rods to the
samples of Al, Cu, C, and Pb. Fill
the bottom of a beaker with
iodine crystals. Touch the
electrodes to the crystals. Do the
same for a beaker containing
sulfur crystals. Record your
observations.
Place a sample of each element
in different test tubes. Add a few
drops of hydrochloric acid to each
test tube. Record the
observations.
Lab #5 – Research Assignment
Assign a three page research paper
on topics related to chemistry. Each
student will be required to use
traditional research sources and
Internet searches.
Math Component: Analysis of
Date
Lab #6 – Atomic Math
Purpose: Calculate the atomic
number of mystery element X by
doing the math.
1)
2)
3)
Post-Viewing Activities
Atoms – Lab #4/Extensions
Students can use their observations
of the physical properties of the
elements to identify unknown
samples of these elements. Three
days after Atom Lab #3, provide the
same samples without labels of their
names. To distinguish the samples,
number the samples. Students can
try to identify the samples as metals
or nonmetals and by name of the
element.
4)
5)
6)
7)
Multiply the atomic number of
Hydrogen by the number of
electrons in Mercury, which
has an atomic number of 80.
Answer ______
Divide this number by the
number of neutrons in
Helium, atomic number 2,
mass number 4.
Answer_______
Add the number of protons in
Potassium, atomic number 19.
Add the mass number of
Carbon.
Answer_______
Subtract the number of
neutrons in Sulfur, atomic
number 16, mass number 32.
Answer_______
Divide by the number of
electrons in Boron, atomic
number 5, mass number 11.
Which of the following
elements is the mystery
element X?
UP AND ATOM
SCIENCE
PATSY PARTIN AND ELANA JONES
A. fluorine; atomic number 9
B. neon; atomic number 10
C. sodium; atomic number 11
Answer_____________
(The final answer is sodium,
atomic number 11)
Action Plan
Organize a class trip to a nearby
university chemistry department to
observe chemistry students in labs.
Share information with other
students on the Internet. Students
will prepare a list of common
household chemicals. Students will
research and report (via Internet) on
the uses, chemical formulas, and
chemical names of these substances.
Extensions
Language Arts/Reading
Prepare written reports summarizing
what has been learned about
compounds, formulas, and ratios of
these elements in compounds. Give
oral presentations from the written
reports to other classes. Encourage
students to write essays on lab
safety.
Study the biographies of Marie Curie,
Ernest Rutherford, Bohr, and
Mendeleev.
Mathematics
Provide practice in atomic
calculations. Compute density and
GRADES 7-8
specific gravity for several
substances. Calculate volume.
UP AND ATOM
SCIENCE
GRADES 7-8
PATSY PARTIN AND ELANA JONES
Art
Make models of isotopes.
Draw compounds showing molecular
arrangement and movement.
Social Studies
Describe history of atomic models.
Note the advantages and
disadvantages of each form of the
Periodic Table proposed in the
twentieth century.
Investigate the historical events that
occurred during Mendeleev’s lifetime
(1804-1907) when his systematic
study of the properties of elements
led to the Periodic Law.
Resources
Internet
Alexander Arrangement of the
Elements (3-D Model)
www.periodictable.com
American Chemical Society
www.acs.org
Atomic Model
http://pc65.frontier.osrhe.edu/HS/SCIENCE/pmo
del.htm
Chemistry 4 Kids
www.chem4kids.com
Chemistry Internet Resources
www.canby.com/~hemphill/chem.html
Interactive Periodic Table
www.shef.ac.uk/~chem/web-elements/
Periodic Tables
www.yahoo.com/science/chemistry/Periodic_
Table_of_the_Elements
Periodic Table of Comic Books
www.uky.edu/~holler/periodic/o.html
Periodic Table-Pictorial Visual
Interpretation
www.chemsoc.org/viselements/
Sensational Slime Site
http://www.eecs.umich.edu/~coaltn/
sciedooutreach/funexperiments/quickndirty/
eric/slime.html
Web Elements
http://www.shef.ac.uk/chemistry/webelements/webelements/elements/text/key/Au
ITV Series
Eureka #116 “Molecules in Solids”
Eureka #117 “Molecules in
Liquids”
UP AND ATOM
SCIENCE
GRADES 7-8
PATSY PARTIN AND ELANA JONES
Name________________________________________________________
LAB #3 WORKSHEET
ACTIVITY GOAL: “WHAT ARE SOME PROPERTIES OF METALS AND
NONMETALS?”
Data and Observations:
Element
Physical
Properties
Malleability
Conductivity
Acid
Al
Cu
Fe
C
S
I
Sn
Pb
Zn
Questions and Conclusions:
1. Based on testing, which of the samples were metals and which were
nonmetals? Explain the answers. (Metals: Al, Cu, Fe / similar results; Nonmetals:
C, S, I /similar results)
2. Why can metals be pounded without breaking? (because they are malleable: it
may be too advanced to discuss metallic crystal structure at this middle school level)
3. What other common elements could be tested with these methods?(various
answers)