Heat
Lynnette Millner Robert H. Lawrence School for Math & Science
9928 S. Crandon Ave.
Chicago IL 60617
(312) 535-6320
Objectives:
The objectives of the HEAT Mini-teach is for the students to gain knowledge
of heat, participate in hands on activities, and to learn the various vocabulary
words associated with heat. This Mini-teach is geared for children in the
intermediate grades (3-6) and should be done in a science laboratory in groups
of 3 or 4.
This Mini-teach is over a span of two weeks. The vocabulary words should be
introduced the first week and one activity should be done each day thereafter.
Vocabulary words:
heat procedure measure kinetic
transfer materials bunsen burner conduction
temperature results energy convection
substance stretch observe radiation
molecules aluminum particles infared rays
Key people to research: Benjamin Thompson, bka Count Rumford
James Prescott Joule
Title: Hot Band
Materials: rubber bands
Procedure: Place the rubber band on your forehead and note the band's
temperature; hold the rubber band between your thumbs and index fingers with
your thumbs touching, stretch the rubber band, quickly touch the stretched band
to your forehead.
Results: The stretched rubber band feels warm.
Why? The rubber band is made of molecules similar to a spring. You pulled the
molecules apart and then they sprung back together quickly hitting one another.
This is a form of mechanical energy.
Title: Cold Hand
Materials: aluminum foil and a throw rug or thick towel
Procedure: Place a piece of foil on the table and a thick towel next to it. Put
one hand on the aluminum and the other on the towel. Observe the different
temperatures.
Results: The metal feels colder than the towel.
Why? The aluminum foil allowed the heat to move through it whereas the towel
did not. The things feel cold to the touch when heat energy is drawn away from
your skin; things feel warm when heat energy is transferred to your skin.
Title: How Heat Blows Up A Balloon
Materials: balloons, glass bottles, bunsen burner or candle, tongs
Procedure: Stretch the balloon over the neck of an empty bottle. Put the bottle
on the net on top of the bunsen burner or set it over a candle using the tongs.
Remove the bottle after 3-5 minutes and notice the before and after results.
Results: The balloon blows up while over the heat and deflate when taken away
from the heat.
Why? When heat is added, the molecules of air in the bottle move faster and
farther apart. The gas (air) occupies more space. As more and more air flows
into the balloon from the bottle, the walls of the elastic balloon are pushed
out by the air. Heat has caused the air to expand.
Title: Heating Water in a Paper Pan
Materials: paper, paper clips, ruler, pencil, measuring cup for water, bunsen
burner or candle, paper towels for cleaning or spillages
Procedure: Measure one inch on all four sides of your paper. Mark them with the
pencil. It should form a square. Fold the edges of the paper to form sides of
an inch high. Fasten the corners with paper clips. Pour about an half of a
inch of water in the paper pan. Place your paper pan of water on the net on top
of the bunsen burner or candle.
Results: The water got warm but the paper pan did not burn.
Why? The water is a good conductor and was able to carry away the heat before
the paper could ignite.
Title: Explosive (POPCORN)
Materials: unpopped popcorn, hot air popcorn popper, bowl, a cup and paper
towels for taking the popped corn back to their desks to eat
Procedure: Observe the shape and size of a few unpopped corn kernels. Place
some popcorn into the tray and release it slowly into the popper. (Make sure
the hot air popcorn popper is ON.)
Results: The corn kernels change from small, hard, yellow kernels to large,
soft, white, ball-shaped structures.
Why? The inside of a corn kernel is filled with starch and water. As the
kernel is heated, the liquid water evaporates-changes to gas. The gas expands
and pushes so hard that it breaks and the starch is blown outward. That is why
you hear the popping noise when popcorn is popping.
Performance Assessment:
Cooperative grouping and evaluation based on their ability to come up with good
explanations and filling out an observation sheet. The sheet can be set up
similar to the way it is written up leaving the spaces blank. For example:
Title:
Materials:
Procedure:
Results and Why?:
Conclusion:
Heat is energy that is transferred between two things because of a
temperature difference. Heat flows on its own from a hotter to a cooler
substance, regardless of the amount of each substance. Heat is commonly
measured in calories, although the joule is preferred.
Specific heat is a measure of how much heat is required to raise the
temperature of a unit of mass of a substance by one degree. Water has a much
higher specific heat than almost anything else. The high specific heat of water
is responsible for the differences in climates between the East and West Coasts.
Heat isn't a thing. It doesn't occupy space nor does it have weight. Heat
is energy that raises the temperature of a thing by causing the molecules in
that thing to move faster.
THIS IS HEAT!!!!!!!!
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