Eat Iron Presentation

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SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-on Activity Training
TeachEngineering Hands-on Activity:
*Eat Iron?!!
TeachEngineering Digital Library:
teachengineering.org
http://commons.wikimedia.org/wiki/File:Iron_electrolytic_and_1cm3_cube.jpg
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
TeachEngineering Digital Library
http://www.teachengineering.org
• The TeachEngineering digital library provides free,
teacher-tested, standards-based engineering
content for K-12 teachers to use in science and
math classrooms.
• Engineering lessons connect real-world experiences
with curricular content already taught in K-12
classrooms.
• Mapped to educational content standards,
TeachEngineering's comprehensive curricula are
hands-on, inexpensive, and relevant to children's
daily lives.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
General Advice
• Be prepared! Do each activity beforehand
• Make sure all materials are available
• Keep students on task
• Follow the time frame
• Be flexible
• Have Fun!!
http://oregonstate.edu/engr/magnetics/magnetic-toys-and-demonstrations
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Full Activity on TeachEngineering
• Mixtures and separation of mixtures
o Iron in breakfast cereal!
• Engineering focus:
o Engineering Research
• Testing and analyzing materials
• Relating science knowledge to engineering applications
• Learning objectives:
o Distinguish and describe the three types of matter:
elements, compounds and mixtures
o Explain the properties of each type of matter and provide
an example of each type.
o Define pure and impure materials.
o Explain how engineers use the magnet separation
technique to separate ferrous and nonferrous materials.
http://www.ars.usda.gov/is/pr/2005/050512.htm
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
• Suggested time: 30 minutes
• Suggested group size: 2-4
students/group
• Materials:
• Big dish
• Access to water
• Iron-fortified flake cereal
(ex: Total [recommended], Special K)
• Strong magnet
• Clear plastic cup
• Plastic spoon
• Blender (if unavailable, large Ziploc
bags)
http://www.finedininglovers.com/video/on-the-web/food-science-extract-iron-from-cereal/
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Engineering Connection (Real World Application):
• Focus on the understanding of mixtures, and how they are characterized by
methods of separation, including:
o
o
o
o
Filtration
Evaporation
Sublimation
Magnetic separation
• Important in chemical and petroleum engineering to separate mixtures into
distinct components
o More than one method may be necessary!
o Includes separating components of crude oil into purified hydrocarbons, used for
natural gases, gasoline, diesel, jet fuel, etc.
• Separation is important in environment engineering for water purification,
also!
• Separation methods vary based on size, shape, mass or chemical affinity
between the constituents of the mixture.
• In this activity, magnetic separation uses magnets to separate iron particles
from a mixture.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Vocabulary Terms
Definitions
Element:
A substance consisting of one type of atom.
Mixture:
A substance consisting of two or more materials.
Compound:
A pure chemical substance consisting of two or more different chemical elements.
Homogeneous mixture:
A mixture that has a uniform appearance and composition throughout its mass.
Heterogeneous mixture:
A mixture composed of visibly different substances or phases.
http://campbellms.typepad.com/ann_dubick/2013/09/elements-compounds-and-mixtures.html/
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Activity Background Concepts:
o Elements are fundamental substances that cannot be further reduced to
simpler substances by ordinary processes and are composed of only one
type of atom. All matter is made up of elements. The elements are classified
as pure substances.
o Compounds are another class of pure substances. A compound is a
material composed of two or more different atoms that are chemically
bonded to one another. That means that it cannot be separated into its
constituents by mechanical or physical means.
o Mixtures are classified as impure substances. A mixture is a material
containing two or more elements or compounds that are in close contact
and are mixed in any proportion. For example, air, sea water, crude oil, etc.
The constituents of a mixture can be separated by physical means, such as
filtration, evaporation, sublimation and magnetic separation.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Activity Background Concepts (cont.):
o Examples of mixtures:
•
•
•
•
•
•
Solid in liquid: sugar and coffee
Liquid in liquid: water and alcohol
Gas in liquid: soda
Gas in solid: air entrapped in soil
Gas in gas: air containing hydrogen, oxygen, nitrogen, carbon dioxide, etc.
Solid in solid: metal alloys
o A homogeneous mixture has the same uniform appearance and
composition throughout its mass. For example, sugar or salt dissolved in
water, alcohol in water, etc.
o A heterogeneous mixture consists of visibly different substances or phases.
A heterogeneous mixture does not have a uniform composition
throughout its mass (its components are distributed unevenly), like the
raisins and flakes in a raisin bran cereal.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Activity Background Concepts (cont.):
o In engineering, a separation process is used to transform a mixture of
substances into two or more distinct products.
• This is done by taking advantage of the fact that the different components of a
mixture probably have different properties such as: size, density, solubility, boiling
point, etc.
o What are some separation techniques for mixtures used in engineering?
• Filtration: separates solids from fluids using a medium through which only the fluid
can pass
• Distillation: separates mixtures of liquids that have different boiling points
• Chromatography: separates dissolved substances traveling through a material
• Centrifugation: separates materials based on different densities
• Drying: removes liquids from solids by vaporization
• Magnetic separation: uses magnets to pull iron particles from mixtures
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Before the Activity:
o Gather materials
o Prepare the cereal by placing ~2 cups of water and 2 cups of cereal in a
blender. Let it sit for a few minutes until the cereal is soft, then blend to
make a smooth and shake-like slurry.
o Divide students into groups of 2-4
Activity Procedure:
o Show students a box of iron-fortified cereal flakes and pose the question:
• If you look at the nutritional label on the box of this cereal, you'll see
that it contains some amounts of iron in its elemental form. Does that
mean that it would be attracted to a magnet? What do you think?
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Activity Procedure (cont.):
o Give a few cereal flakes and a magnet to each group and ask them to try
to move the flakes with the magnet. (The flakes will not move!)
o Discuss why nothing happened (possible reasons: the flake is too big, not
enough iron in the flakes, too much friction to overcome, magnet not
strong enough), and ask what might be done to overcome some of these
issues. (Float the flake on water!)
o Direct groups to place a big dish on their tables and completely fill them
with water, above the rim. Very slowly put a big cereal flake on the water
surface, near the middle.
o Ask the groups to try using the magnets now. Direct them to put the
magnet very close to the cereal flake and move the magnet very slowly in
one direction.
o Oh yaaaa!!!! Expect students to see that the flake moves! To verify that its
movement is due to the magnet, slowly change the direction the magnet
is moving. If the cereal follows the magnet, then it is because of the iron
present in the cereal.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Activity Procedure (cont.):
o Ask students some question related to the iron in the cereal:
• Is cereal a compound or a mixture? (mixture)
• Do its ingredients keep their individual properties? (yes)
• Is this helpful for separating components of the mixture? (yes)
o Make the following points:
• The individual components in mixtures retain their own physical properties.
• This conservation of properties can be taken advantage of to separate out
components from a mixture.
• A homogeneous mixture is one in which the components are evenly
distributed. A heterogeneous mixture has uneven distribution of its
components. Breakfast cereals are good examples of heterogeneous
mixtures (think of the raisins and flakes in a raisin bran cereal).
• Iron in its elemental form is strongly attracted to magnets. Compounds of
iron are not as strongly attracted to magnets.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Activity Procedure (cont.):
o Pour samples of the already-prepared cereal slurry into clear plastic cups,
one for each group.
o Direct groups to have one student hold a magnet against the outside of
the cup about midway up, while another student uses the plastic spoon to
gently stir the slurry for 20-30 seconds.
o What happens? Expect to see a black line appear on the cup wall, which
is the iron particles being stopped close to the magnet.
o Conclude with a class discussion that makes the point that using magnets is
a useful way to separate iron from mixtures:
• It is the very same way that recycling centers use magnets to separate
cans from plastic and cardboard
• Materials engineers use magnets to separate ferrous from nonferrous
materials.
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Eat Iron?!!
Teaching tips:
o Most important!!! Test this activity before teaching!!!!
• Not every type of cereal works
• Iron filaments are extremely small – it helps to know what you are
looking for!
o Emphasize the science concepts, vocabulary, and engineering
connection; reinforce these throughout the activity
o Encourage students to come up with ideas on how to separate the
iron from the cereal… help lead them to the answer!
o Be familiar with background concepts, especially real world
engineering applications, to answer questions
o The video at this site is a great resource for this activity:
http://www.finedininglovers.com/video/on-the-web/food-scienceextract-iron-from-cereal/
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
Activity Takeaways
• Teambuilding skills
o Making decisions, sharing tasks and materials
• Engineering connections
o Encourage students to learn science concepts by providing examples
of real world engineering applications
• Encouragement to be problemsolvers and creative thinkers
o Help students develop a solution to separating
iron from cereal
o Promote creative thinking and brainstorming
• Motivation through having fun
o Introduce the activity as a fun learning
experience!
http://www.buckeyeaz.gov/index.aspx?nid=163
SHPE Foundation
SHPE Jr. Chapter Curriculum
Hands-On Activity Training
TeachEngineering Contact Information
• TeachEngineering: http://www.teachengineering.org/
o over 1,200 standards-based engineering lessons and activities
• Carleigh Samson, TeachEngineering Editor
o carleigh.samson@colorado.edu
o 303.492.6950
Questions?
http://www.fws.gov/refuge/Stone_Lakes/FAQ.html/
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