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!!!!!!!!