Download LESSON 18: Magnetic Metals

LESSON 18: Magnetic Metals
ESTIMATED TIME Setup: 5 minutes | Procedure: 5–10 minutes
• DESCRIPTION
• MATERIALS
Use a magnet to determine which types of metal
objects are and are not attracted to it.
• OBJECTIVE
This lesson introduces forces of attraction, specifically
magnetism, demonstrating that not all metals are
attracted to magnets. Students place metal items on a
desk and move a magnet near those metal items. The
lesson can be extended to address other properties of
metals.
• CONTENT TOPICS
Scientific inquiry; properties of matter; attractive
forces (magnetism); metals
Magnet (refrigerator variety will work)
or stiff plastic ruler
o Clear plastic tape
o Assorted metal objects (key, metal paper clip,
metal spoon, aluminum foil ball, hair pin, safety
pin, penny, nickel, dime, quarter, nail, metal
bottle cap, etc.)
o
o Wood
Always remember to use the appropriate safety
equipment when conducting your experiment.
Refer to the Safety First section in the Resource Guide
on pages 391–393 for more detailed information about
safety in the classroom.
Jump ahead to page 235 to view the
Experimental Procedure.
NATIONAL SCIENCE EDUCATION STANDARDS SUBJECT MATTER
This lesson applies both Dimension 1: Scientific and Engineering Practices and Dimension 2: Crosscutting Concepts
from “A Framework for K–12 Science Education,” established as a guide for the updated National Science Education
Standards. In addition, this lesson covers the following Disciplinary Core Ideas from that framework:
• PS1.A: Structure and Properties of Matter
• ETS2.A: Interdependence of Science, Engineering, and Technology (see Analysis & Conclusion)
• ETS2.B: Influence of Engineering, Technology, and Science on Society and the Natural World
(see Analysis & Conclusion)
OBSERVATION & RESEARCH
BACKGROUND
Scientists often classify elements as either metals or
nonmetals. Metals are primarily found on the left side of
the periodic table. They are usually solid at a normal room
temperature of about 75 °F and have a shiny appearance.
Other usual properties of metals include good thermal and
electrical conductivity and the ability to be reshaped or
hammered thin (known as malleability and ductility,
respectively). Nonmetals are usually found on the right
side of the periodic table and are generally gases or solids
at a normal room temperature. Semi-metals (metalloids)
are located between metals and nonmetals on the periodic
table and have some properties of both.
Magnetism is a unique property of some metal elements
but not all. Magnetism is a force of attraction or
repulsion between materials that acts at a distance
through a magnetic field (region of magnetic force).
Some magnets have a stronger magnetic force than others.
Force measures the amount of push or pull on an object.
Many other forces exist on the earth, such as gravity and
intramolecular forces (chemical bonds).
A magnet is an object that creates a strong magnetic field.
Only certain metals produce a magnetic field. These metals
include iron, nickel, and cobalt. All magnets are made of
these metals, called ferromagnetic metals.
You Be TheLESSON
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Activity
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| page 232
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232
LESSON 18: Magnetic Metals
The ends of a magnet are called its poles, where the
magnetic forces are the strongest. All magnets have two
poles, a north pole (N) and a south pole (S). Magnets
will be attracted by their opposite poles and repelled by
like poles. For example, the north pole of one magnet
will attract the south pole of another magnet, but the
north poles of two magnets will repel each other (as will
the two south poles). Therefore, metals with magnetic
properties will be attracted to a magnet. Specifically, the
north pole of a magnetic metal will be attracted to the
south pole of a magnet and vice versa.
In this experiment, students explore magnetism by using
magnets to test which metals produce a magnetic field.
Metal objects that produce a magnetic field will be
attracted to the magnet, while metals that do not produce
a magnetic field will not be attracted to the magnet.
For example, paper clips generally contain iron, and
therefore will be attracted to a magnet. On the other hand,
U.S. pennies are made primarily of zinc with a copper
coating, and therefore will not be attracted to the magnet.
FORMULAS & EQUATIONS
Iron is one of the most abundant metals on the earth,
forming about 5.6% of the earth’s crust.
CONNECT TO THE YOU BE THE
CHEMIST CHALLENGE
For additional background information, please
review CEF’s Challenge study materials online at
http://www.chemed.org/ybtc/challenge/study.aspx.
• Additional information on metals, nonmetals, and
semi-metals can be found in the Periodic Table
section of CEF’s Passport to Science Exploration:
The Core of Chemistry.
• Additional information on forces, such as
magnetism, can be found in the Forces of
Attraction section of CEF’s Passport to Science
Exploration: Chemistry Connections.
HYPOTHESIS
uSome metal objects produce a magnetic
field and will be attracted to magnets, while
others will not.
The chemical symbol for iron is Fe.
Its atomic number is 26, and its atomic weight is
approximately 55.8 atomic mass units (amu). Iron is
alloyed with carbon to create steel. Most metal paper clips
are made of steel.
Cobalt is an essential part of vitamin B12.
The chemical symbol for cobalt is Co.
Its atomic number is 27, and its atomic weight is
approximately 58.9 amu.
Fun Fact
A naturally magnetic mineral
commonly called lodestone
was used in the past to make
magnetic compass needles.
The word “lode” means “lead”
because the compasses
were used to lead
sailors home.
Nickel is a silvery white metal with a high polish.
The chemical symbol for nickel is Ni.
Its atomic number is 28, and its atomic weight is
approximately 58.7 amu.
You Be The Chemist® Activity Guide | page 233
LESSON 18: Magnetic Metals
DIFFERENTIATION IN THE CLASSROOM
LOWER GRADE LEVELS/BEGINNERS
Conduct the experiment as described on page 235, but
focus the lesson on classifying matter. Discuss physical
properties and the different uses of different substances.
Physical properties can be observed by using our senses
and taking measurements. Some examples of physical
properties are color, shape, boiling point, melting point, and
density. Have students practice classifying matter based on
physical properties. Point out different objects in the room,
and ask the students to describe their physical properties
and group substances with similar properties together.
Ask them to compare and contrast the physical properties
of the assorted materials used in the lesson.
HIGHER GRADE LEVELS/ADVANCED STUDENTS
DESCRIPTION
Use a magnet to determine which metal objects are and
are not attracted to it.
OBJECTIVE
This lesson introduces properties of metals and forces of
attraction, specifically magnetism, and demonstrates that
not all metals are attracted to magnets.
OBSERVATION & RESEARCH
Scientists often classify elements as either metals or
nonmetals. Metals are primarily found on the left side of
the periodic table. They are usually solid at a normal
room temperature of about 75 °F and have a shiny
appearance. Other usual properties of metals include
good thermal and electrical conductivity, malleability,
and ductility. Electrical conductivity is a measure of the
ease with which electricity can travel through a material.
Thermal conductivity is a measure of the ease with which
thermal energy can travel through a material. Malleability
is the ability of a metal to be flattened, shaped, or
formed, without breaking, when pressure is applied.
Ductility is the ability of a metal to be stretched into a thin
wire or thread without breaking. Additionally, luster is
the ability of a metal to reflect light, which gives metals
their shiny appearance.
Magnetism is a unique property of some metal elements,
but not all. Magnetism is a force of attraction or repulsion
between materials that acts at a distance through a
magnetic field (region of magnetic force). Some magnets
have a stronger magnetic force than others. Force
measures the amount of push or pull on an object. Many
other forces exist on the earth, such as gravity and
intramolecular forces (chemical bonds).
A magnet is an object that creates a strong magnetic field.
Only certain metals produce a magnetic field. These metals
include iron, nickel, and cobalt. All magnets are made of
these metals, called ferromagnetic metals. There are two
basic kinds of magnets—permanent and temporary.
A permanent magnet keeps a certain level of magnetism
for a long time. A temporary magnet acts like a permanent
magnet when it is within a strong magnetic field but loses
its magnetism when the magnetic field is removed.
Any object that is lifted or moved by a magnet acts as a
temporary magnet, but generally it loses its magnetism
when the permanent magnet is removed. However, in some
cases the magnetized object will retain weak magnetic
properties.
The ends of a magnet are called its poles, where the
magnetic forces are the strongest. All magnets have two
poles, a north pole (N) and a south pole (S).
CONNECT TO THE YOU BE THE
CHEMIST CHALLENGE
For additional background information, please
review CEF’s Challenge study materials online at
http://www.chemed.org/ybtc/challenge/study.aspx.
• Additional information on metals, nonmetals, and
semi-metals can be found in the Atomic Structure
and Periodic Table sections of CEF’s Passport to
Science Exploration: The Core of Chemistry.
• Additional information on forces, such as
magnetism, can be found in the Forces of
Attraction section of CEF’s Passport to Science
Exploration: Chemistry Connections.
• Additional information on metallic properties
can be found in the Forces of Attraction section of
CEF’s Passport to Science Exploration: Chemistry
Connections.
You Be The Chemist® Activity Guide | page 234
LESSON 18: Magnetic Metals
DIFFERENTIATION IN THE CLASSROOM
Magnets will be attracted by their opposite poles and
repelled by like poles. For example, the north pole of one
magnet will attract the south pole of another magnet, but
the north poles of two magnets will repel each other (as
will the two south poles). Therefore, metals with
magnetic properties will be attracted to a magnet.
(Specifically, the north end of a magnetic metal will be
attracted to the south pole of a magnet and vice versa.)
In this experiment, students explore magnetism by using
permanent magnets to test which metals produce a magnetic
field. Metal objects that produce a magnetic field will be
attracted to the magnet, while metals that do not produce a
magnetic field will not be attracted to the magnet. For
example, paper clips generally contain iron, and therefore
will be attracted to a magnet. On the other hand, U.S.
pennies are made primarily of zinc with a copper coating,
and therefore will not be attracted to the magnet.
EXPERIMENTATION
As the students perform the experiment, challenge them to identify the independent, dependent, and controlled variables,
as well as whether there is a control setup for the experiment. (Hint: If the type of metal object is changed, will it react
differently to the magnet.) Review the information in the Scientific Inquiry section on pages 14–16 to discuss variables.
NOTES
EXPERIMENTAL PROCEDURE
1. Use tape to attach a magnet to the end of
the ruler so that the magnet is facing away from
the ruler. Do not cover the magnetic surface with
the tape. (You do not need to remove the magnet
from its decorative casing.)
2. Place your metal objects in a row, and predict
which metals will be attracted to the magnet and
which will not.
3. Hold the magnet over each item, and record which
items are attracted to the magnet. Go back over the
objects that were not affected by the magnet one
more time just in case you missed any.
DATA COLLECTION
Have students record data in their science notebooks or on
the following activity sheet. Which objects were attracted
to the magnet? Which objects were not attracted to the
magnet? You can use the table in the activity sheet (or a
similar one of your own) for students to record their data.
You Be The Chemist® Activity Guide | page 235
LESSON 18: Magnetic Metals
ANALYSIS & CONCLUSION
Use the questions from the activity sheet or your own
questions to discuss the experimental data. Ask students
to determine whether they should accept or reject their
hypotheses. Review the information in the Scientific
Inquiry section on pages 14–16 to discuss valid and
invalid hypotheses.
ASSESSMENT/GOALS
Upon completion of this lesson, students should be able
to …
• Apply a scientific inquiry process and perform an
experiment.
• Identify general properties of metals.
• Explain magnetism and identify magnetic elements.
• Describe forces of attraction and repulsion and how
they relate to magnetic poles.
• Compare and contrast permanent and temporary
magnets (see Differentiation in the Classroom).
REAL-WORLD APPLICATIONS
• Metal paper clips are generally made from steel wire.
Steel is an alloy of iron and carbon. The iron in the
paper clips causes them to be attracted to the magnet.
• The mineral magnetite, also known as lodestone, is a
natural magnet. Small iron particles are often found
clinging to the surface of the magnetite stones.
Even though it is a relatively weak magnet, it can
attract large steel nails.
• Magnets and magnetic technology have been widely
used in the mining industry. Powerful magnets are
used to separate valuable materials from within the
mine. They are also used to remove contaminants
from the mined materials, such as coal.
COMMUNICATION
Discuss the results as a class and review the activity sheet.
Review the information in the Scientific Inquiry section on
pages 14–16 to discuss the importance of communication
to scientific progress.
MODIFICATIONS/EXTENSIONS
Modifications and extensions provide alternative methods
for performing the lesson or similar lessons. They also
introduce ways to expand on the content topics presented
and think beyond those topics. Use the following
examples or have a discussion to generate other ideas
as a class.
• Take the experiment one step further. Use one of the
objects that was attracted to the magnet, and place it
on the magnet for about a minute. Next, remove the
object from the magnet, and see if it can attract your
other magnetic objects. Metals that are magnetic can
be made into temporary magnets themselves!
K-4
See Lesson 2: Steamy Metals for a unit on metals or
classifying matter.
You Be The Chemist® Activity Guide | page 236
LESSON 18 ACTIVITY SHEET: Magnetic Metals
OBSERVE & RESEARCH
1. Write down the materials you see. ____________________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
2. How might these materials be used? __________________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
3. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term
Definition
Example (write or add image)
Metals
Nonmetals
Semi-metals
Magnetism
Force
Poles
4. Consider whether different metal objects are or are not attracted to magnets and why.
uWrite your hypothesis. ______________________________________________________________
______________________________________________________________________________________
______________________________________________________________________________________
You Be The Chemist®Activity
ActivityGuides
Guide | page 237
LESSON 18 ACTIVITY SHEET: Magnetic Metals
PERFORM YOUR EXPERIMENT
1. Use tape to attach a magnet to the end of the ruler. Do not cover the magnetic surface with tape. The magnet
should face away from the ruler. You do not need to remove the magnet from its cover.
2. Place your metal objects in a row. Predict which metals will be attracted to the magnet and which will not.
3. Hold the magnet over each item. Record which items are attracted to the magnet. Go back over the objects that
were not affected by the magnet one more time just in case you missed any.
ANALYZE & CONCLUDE
1. In the table below, list all of the objects you will test. Then, record your predictions. (Which objects do you think are
magnetic and which are not?) In the last column, record the results. (Which objects were attracted to the magnet?)
Object
Prediction
You Be The Chemist® Activity Guide | page 238
Results
LESSON 18 ACTIVITY SHEET: Magnetic Metals
2. Describe the metal objects. How are they similar? How are they different?
__________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
3. Do similar poles of two magnets attract or repel each other?
____________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
4. What happens when you move the magnet over the metal objects?
________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
5. Magnets have two poles. What are they called?
________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
6. Is your hypothesis valid? Why or why not? If not, what would be your next steps?
__________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
You Be The Chemist®Activity
ActivityGuides
Guide | page 239
LESSON 18 ACTIVITY SHEET: Magnetic Metals
EXPAND YOUR KNOWLEDGE—ADVANCED
1. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term
Definition
Example (write or add image)
Electrical conductivity
Thermal conductivity
Malleability
Ductility
Luster
Permanent magnet
Temporary magnet
2. What happens when you place a magnetic metal on the magnet for a minute and then move it over other metal
objects? Why? ________________________________________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
You Be The Chemist® Activity Guide | page 240
LESSON 18 ACTIVITY SHEET: Magnetic Metals
ANSWER KEY Below are suggested answers. Other answers may also be acceptable.
OBSERVE & RESEARCH
Magnet, ruler, tape, keys, paper clips, coins …
1. Write down the materials you see. ____________________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
Magnets may be used to attract different metals. A ruler may be used to measure. Tape may
2. How might these materials be used? __________________________________________________________________
be used to hold something in place. Keys may be used to open doors. Paper clips may be used to hold paper together. Coins may be used as
______________________________________________________________________________________________________
money. The magnet may be used to test the magnetic properties of different metal objects.
______________________________________________________________________________________________________
3. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term
Definition
Metals
A set of elements that are usually solid at a normal
room temperature and are found primarily on the
left side of the periodic table.
Nonmetals
A set of elements that are generally gases or solids
at a normal room temperature and are found
primarily on the right side of the periodic table.
Semi-metals
A set of elements that have some properties of
both metals and nonmetals and are found along a
zigzag dividing line between metals and nonmetals
on the periodic table; also known as metalloids.
Magnetism
A force of attraction or repulsion between materials
that produce a magnetic field.
Force
A push or pull acting on an object, sometimes
causing a change in position or motion.
Poles
The ends of a magnet, each having an opposite
charge, one positive and one negative; these poles
are called the north pole and the south pole.
Example (write or add image)
4. Consider whether different metal objects are or are not attracted to magnets and why.
Some metals objects have magnetic properties (produce a magnetic field) and will be
uWrite your hypothesis. ______________________________________________________________
attracted to magnets. Other metals do not have magnetic properties, so they are not attracted to magnets.
______________________________________________________________________________________
______________________________________________________________________________________
You Be The Chemist® Activity Guide | page 241
LESSON 18 ACTIVITY SHEET: Magnetic Metals
ANSWER KEY Below are suggested answers. Other answers may also be acceptable.
PERFORM YOUR EXPERIMENT
1. Use tape to attach a magnet to the end of the ruler. Do not cover the magnetic surface with tape. The magnet
should face away from the ruler. You do not need to remove the magnet from its cover.
2. Place your metal objects in a row. Predict which metals will be attracted to the magnet and which will not.
3. Hold the magnet over each item. Record which items are attracted to the magnet. Go back over the objects that
were not affected by the magnet one more time just in case you missed any.
ANALYZE & CONCLUDE
1. In the table below, list all of the objects you will test. Then, record your predictions. (Which objects do you think are
magnetic and which are not?) In the last column, record the results. (Which objects were attracted to the magnet?)
Object
Prediction
Results
Answers will vary
Answers will vary
Answers will vary
You Be The Chemist® Activity Guide | page 242
LESSON 18 ACTIVITY SHEET: Magnetic Metals
ANSWER KEY Below are suggested answers. Other answers may also be acceptable.
2. Describe the metal objects. How are they similar? How are they different?
Most of the metal objects are sturdy and hard.
__________________________________
Many are a grayish silver color, while others are reddish orange or yellow. Most of the metals are shiny.
______________________________________________________________________________________________________
______________________________________________________________________________________________________
3. Do similar poles of two magnets attract or repel each other?
Similar poles of two magnets repel each other. Opposite poles
____________________________________________
attract each other.
______________________________________________________________________________________________________
______________________________________________________________________________________________________
4. What happens when you move the magnet over the metal objects?
Certain metals are attracted to the magnet. They will rise
________________________________________
and attach to the magnet.
______________________________________________________________________________________________________
______________________________________________________________________________________________________
5. Magnets have two poles. What are they called?
The two poles are called the north pole (N) and the south pole (S).
________________________________________________________
______________________________________________________________________________________________________
______________________________________________________________________________________________________
6. Is your hypothesis valid? Why or why not? If not, what would be your next steps?
__________________________
Answer 1: Valid because the data support my hypothesis.
______________________________________________________________________________________________________
Answer 2: Invalid because the data do not support my hypothesis. I would reject my hypothesis and could form a new one, such as …
______________________________________________________________________________________________________
You Be The Chemist® Activity Guide | page 243
LESSON 18 ACTIVITY SHEET: Magnetic Metals
ANSWER KEY Below are suggested answers. Other answers may also be acceptable.
EXPAND YOUR KNOWLEDGE—ADVANCED
Have students complete this section if you used the advanced differentiation information, or challenge them to find the answers to these
questions at home and discuss how these terms relate to the experiment in class the next day.
1. Define the following key terms. Then, provide an example of each by writing the example or drawing/pasting an
image of the example.
Term
Definition
Electrical conductivity
A measure of the ease with which electricity can travel
through a material.
Thermal conductivity
The measure of the rate at which thermal energy can
travel through a material.
Malleability
The ability of a metal to be flattened, shaped, or
formed without breaking when pressure is applied.
Ductility
The ability of a metal to be stretched into a thin wire or
thread without breaking.
Luster
The ability of a metal to reflect light; this property gives
metals a shiny appearance.
Permanent magnet
A type of magnetic substance that keeps a certain
level of magnetism for a long time.
Temporary magnet
A type of magnet that acts like a permanent magnet
when it is within a strong magnetic field but loses its
magnetism when the magnetic field is removed.
Example (write or add image)
2. What happens when you place a magnetic metal on the magnet for a minute and then move it over other metal
If you place a magnetic metal on a magnet, it will act as a temporary magnet for a short time until the magnetic field is
objects? Why? ________________________________________________________________________________________
removed. It will be attracted to other magnetic objects while it is a temporary magnet.
______________________________________________________________________________________________________
______________________________________________________________________________________________________
You Be The Chemist® Activity Guide | page 244