Changing States: Does it

Matter? Substances change around us all the time. Substances can undergo physical or chemical

changes. It all depends upon the chemical make-up and what is done to the substance.

Volcanic Eruption

How many of you have seen volcanoes explode at science fairs?  Do you know how it works?  

Can you tell what type of reaction it is, physical or chemical?  Let’s take a look! 

1. Place an empty water bottle in a pie plate 2. Add ½ cup colored water to bottle 3. Add 3 teaspoons of baking soda to water 4. Put lid on and shake bottle 5. Add a squirt of liquid detergent 6. Slowly add 3 tablespoons vinegar to water (this should make it overflow… if you do not want it to overflow then use 2 teaspoons baking soda and 2 tablespoons vinegar) 7. Pour overflow into container and dry out with a towel

A. What did you observe in the eruption?

______________________________________________________________________________

B. Is the volcanic eruption a chemical or physical change? __________________________

Physical Changes

A change that does not result in the production of a new substance.  Physical changes only alter the form 

(i.e., solid, liquid, gas) or appearance (i.e., size and shape) of the substance.  They are reversible.   

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Examples: water boiling, ice melting, water freezing, change in size, change in shape, change in form

Chemical Changes

A change that results in the formation of a new substance.  Chemical changes are irreversible. 

    ‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐ 

Possible Indicators of a    1.)  color change, 2.)  gas given off, 3.)  a new substance forms, 

Chemical Change:     4.)  heat is given off,  5.)  heat is absorbed   

Practice ~~ Identify each of the following as a Physical (P) or Chemical (C) Change.

1. A piece of wood burns to form ash _____ 2. Water is absorbed by a paper towel _____ 3. A piece of cork is cut in half _____ 4. A bicycle chain rusts _____ 5. Turning brownie mix into brownies _____ 6. A Popsicle melts _____

 

Cleaning Dirty Pennies 

1. Mix 1 tablespoon vinegar and ¼ teaspoon salt together in a bowl. 

2. Dip 1 penny halfway into the mixture and hold for 10 seconds. 

3. Pull the penny out of the solution and see how shiny it is. 

Wow!  How did that happen?  After a while, pennies will oxidize or become dull and 

dark.  This is because of the water and oxygen molecules that they come into contact 

with in the air.  When vinegar is combined with salt it becomes a weak solution of 

hydrochloric acid.  Hydrochloric acid cleans metals like copper.  This is a form of 

chemical change.   

 

Balloon Blow Up 

 1. Pour ½ cup vinegar into a water bottle. 

2. Use a funnel to put ¼ cup baking soda in a balloon. 

3. Stretch balloon over water bottle containing the vinegar.   

Try not to spill any of the baking soda as you attach the balloon. 

4. Transfer the baking soda into the bottle. 

5. Watch as the balloon expands. 

 

What happened in this experiment?  The baking soda and vinegar react, and one of 

the products of the chemical reaction is carbon dioxide gas.  The reaction of baking 

soda to form carbon dioxide gas is the basis of its use as a leavening (rising) agent in 

baking. 

Kitchen Chemistry Chemistry as we know it began in the 1600s.  However, in prehistoric times people believed 

nature and changes in nature were caused by spirits and magic.  Soon after, early man 

discovered fire and heat and how it could change things.  Early scientists (called alchemists) 

discovered compounds and believed that metal could be turned into gold.  However, none of 

them knew how well chemistry really worked. 

 

Chemists today use expensive equipment and harmful chemicals, but you do not have to!  You 

can become a chemist in your own kitchen.  So, grab your lab coat and get ready to do some 

kitchen chemistry. 

 

 

Changing States: Does it Matter?

OBJECTIVES: 

Participants will: 

Explain the difference between a physical and chemical change. 

Identify the 5 factors that indicate if a chemical change has occurred. 

Give at least 3 examples of a physical change. 

Classify a change as either a physical or chemical change. 

 

TN GUIDANCE CURRICULUM STANDARDS MEET: 

 

Science (4th Grade)GLE0407.9.2  Explore the different types of physical changes in  

              matter. 

Science (5th Grade)GLE0507.9.1  Observe and measure the simple chemical properties 

of common substances 

 

INTRODUCTION OF 2012‐2013 4‐H PROGRAM: 

1. Introduce 2012‐2013 4‐H program to students.  This year’s program will deal 

with science.  We will have four science experiments that will help you learn 

about topics in physical science.  This year’s 4‐H programs are: 

Changing States:  Does it Matter? ‐ Students will learn about 

chemical vs. physical changes through hands‐on examples. 

Playing with Polymers‐ Students will investigate a mystery 

polymer and try to make an educated guess as to what it is.  

Discussion on states of matter will also be included.    

Energy in Motion‐ Students will learn about the two categories of 

energy, potential and kinetic.  Students will learn to classify energy 

as potential and kinetic.  Finally, students will learn how energy 

can change forms through a hands‐on science experiment.  

Fun with Friction‐ Students will continue to explore potential 

versus kinetic energy by studying friction and gravity, two forces 

that affect all moving objects on Earth.  

 

 

Changing States: Does it Matter? 

1. Provide an explanation of physical vs. chemical changes. Write differences on board. 

a. Physical Change—A change that does not result in the production of a new 

substance.  Physical changes result only in a change in the form (i.e., solid 

liquid, gas) or appearance of a substance, but not the chemical composition of 

the substance.  The substance will still ultimately be the same.  Once a 

physical change occurs, it can be reversed.   

i. Example—You have some M&M’s.  You have a pile of brown      

M&M’s and a pile of colored M&M’s.  You slowly add the colored 

M&M’s to the brown M&M’s pile.  Did this change result in the 

formation of a new substance.  NO!  The M&M’s are still M&M’s after 

adding the colored ones.  The only difference is the appearance has 

changed.  Could you reverse this change?  YES!  All you have to do is 

take out the colored M&M’s and you would be left with what you 

originally started out with. 

b. Chemical Change‐A change that results in the production of a new and 

different substance.  These changes are often indicated by one of these factors:  

color change, a gas is given off, a new substance if formed, heat is given off, 

and heat is absorbed.  Chemical reactions, once they occur, are irreversible. 

i. Example—I eat an apple.  When I am finished with the apple, I put the 

core in the compost pile.  Over time the apple rots and becomes 

compost material.  This is an example of a chemical change because the 

apple core becomes compost and the reaction cannot be reversed.  

2. Demonstrate the Volcanic Eruption experiment. Have students record observations 

in space provided and guess the type of reaction occurring.  This is an example of a 

chemical reaction that is occurring between the baking soda and the vinegar.  Baking 

soda is used in cooking because it is a leavening agent.  Most types of cooking are a 

chemical reaction. 

3. If time permits, have students use play dough to show a physical change. 

4. Have students practice identifying reactions are chemical (C) or physical (P). 

A piece of wood burns to form ash __C___ Water is absorbed by a paper towel __P___ A piece of cork is cut in half __P___ A bicycle chain rusts __C___ Turning brownie mix into brownies _C___ A Popsicle melts __P___

4.     Alert students to the Kitchen Chemistry section on back of sheet.  There are 2  

        simple chemical reactions that they can do at home.  Remind students that they will  

        be kitchen chemists this month as they make their bread for the 4‐H Bread Baking  

        Contest.  Bread Baking is a chemical reaction. 

WHAT ARE POLYMERS?

To know what a polymer is you need to know what an atom is. An atom is the basic building blocks of matter. Everyone and everything is made of atoms. When you put two or more atoms together, what do you get? You get a molecule! When you put molecules together you get a polymer. Polymers are tiny molecules strung in long repeating chains.

Atom

Molecule

-- -- -- Polymer

Why should you care what a polymer is? Well for one thing, your body is made of them. DNA, the proteins and starches in the foods we eat, the wheels on our skateboards, and the tires on our bikes and cars are all made from polymers. In fact, we’re surrounded by polymers every day, everywhere we go.

What makes polymers so fun is that how they act depends on what kinds of molecules they're made up of and how they're put together. Polymers can be a solid or liquid…or even both at the same time. Remember, a solid will keep its own shape, does not flow, and its molecules are packed closely together. A liquid takes the shape of the container it is in, flows, and its molecules are spread out. Molecules in a gas are very much spread apart.

 

MYSTERY POLYMER

½ teaspoon Mystery Polymer Ziploc Bags ½ cup distilled water 1 teaspoons Salt

What do you think the mystery polymer is? ______________________ What do you think will happen if you add water to the mystery polymer? __________________________________________________________________________________________

The mystery polymer is ____________________. The mystery polymer is the same substance found in __________________.

Making Polymers at Home

Silly Putty Silly Putty® is one of the all time favorite toys. It was invented in 1943. Silly Putty® was originally intended for industrial use as a synthetic rubber but was not usable because it was not as firm as rubber. It was scrapped as a potential product until 1949, when an unemployed advertising executive thought it might be a good idea to market it as a toy. He packaged the substance in plastic eggs, and the familiar plastic egg filled with the mysterious goo has been an American toy icon ever since. Here is how you can make Silly Putty® at home.

You will need:

1 tablespoon Elmer’s® white glue

1 teaspoon water

1 tablespoon powdered Borax®

1 cup Water

Food coloring

Empty Soda Bottle

Plastic zip lock bag

1. Mix 1 tablespoon of Borax® powder and 1 cup of water in an empty soda bottle. 2. Replace the cap and shake the mixture until the Borax has dissolved completely. 3. Next place 1 tablespoon of Elmer’s® white glue in a plastic bag along with 1 teaspoon of

water. Add a couple drops of food coloring to the glue/water mixture. Mix well. 4. Add 1 tablespoon of the Borax/water mixture to the zip lock bag and seal it. Massage

the mixture for a few minutes until it begins to set up. It will gradually take on a putty-like texture as the polymer chains grow and interconnect.

5. When you are able to remove the putty from the bag in one piece, do so and begin rolling it between your fingers. The more you roll it, the more similar it will be to Silly Putty®.

OBJECTIVES: 

Participants will: 

Correctly identify the reaction of the Hydrogel with water as a physical change. 

Name and describe the three states of matter. 

Correctly define what a polymer is. 

 

TN CURRICULUM STANDARDS MEET: 

 

Science (4th Grade)GLE0407.9.2  Explore the different types of physical changes in  

              matter. 

Science (5th Grade)GLE0507.9.1  Observe and measure the simple chemical properties 

of common substances. 

Science (4th Grade)GLE0407.Inq.1 and Science (5th Grade)GLE0507.Inq.1   

Explore different scientific phenomena by asking 

questions, making logical predictions, planning 

investigations, and recording data. 

Science (4th Grade)GLE0407.Inq.2 and Science (5th Grade)GLE0507.Inq.2 

Select and use appropriate tools and simple 

equipment to conduct and investigation. 

 

PLAYING WITH POLYMERS 

1. Introduce lesson by going over background information found on front page. a. Talk about what an atom, molecule, and polymer are.  These concepts can 

be demonstrated on the board with drawings. b. Talk about the two states that a polymer can exist in—solid or liquid.  You 

can draw this on the board.  

 

 

2. Complete Mystery Polymer Activity a. Introduction:  “Today I have brought with me a mystery polymer.  Each of 

you will need to make an educated guess as to what it actually is.” b. Educated Guess:  Measure out ½ a teaspoon of the mystery polymer into a 

zip lock bag.  Walk around the room and have students guess what it is by 

looking, smelling, shaking, etc.  Instruct students not to put the polymer in 

their mouth.  Have students write down what they think the mystery 

polymer is on their sheet. c. Educated Guess:  Have students take a guess at what will happen if water 

is added to the mystery polymer.  Students will record responses on sheet. d. Activity:  Measure out ½ cup of distilled water and pour into the polymer 

powder. Within seconds the powder/water mixture will become a solid. 

3. The mystery polymer is Hydrogel.  Hydrogel, called sodium polyacrylate, was a 

product developed for use in astronaut diapers.  Today, Hydrogel is used in 

baby diapers and a variety of personal products, but in gardening as well.  

Potting soil containing these water‐holding crystals is available at many garden 

centers. 

4. If time permits, tear open a diaper to demonstrate that Hydrogel is actually in the 

diaper. 

5. The change that occurred when water is added to the Hydrogel is a physical 

change.  It is seen as the crystals absorb water.  They expand to many times their 

original size.  If left to dry out over a period of time, the crystals decrease in size 

and return to their normal state.  Because this is a reversible change, then it is a 

physical change.    

6. Add ¼ teaspoon of salt to the solid Hydrogel solution. The salt changes the solid 

back to a liquid solution.  This happens because the salt destroys the polymer’s 

water absorbing abilities. 

 

7. Making Polymers at Home:  On the back of the sheet is an at‐home polymer that 

students can make.  This polymer is Silly Putty.  Instruct students that if they 

want to make their own polymer at home, this is a great recipe to use. 

 

8. Hydrogel Ordering Information:  http://www.stevespanglerscience.com/product/1278 

Important : Do not pour Hydrogel down the sink. Because of its water absorbing capabilities, it will lead to a stopped-up drain.

 

 

 

Energy helps us do things. It gives us light. It warms our bodies and homes. It bakes cakes and keeps milk cold. It runs our TVs and our cars. It makes us grow, move, and think.

Energy is the power to change things. It is the ability to do work. All forms of energy fall under two categories—potential or kinetic energy.

Motion

Stored Mechanical Heat (Thermal)

Nuclear Sound

Chemical Light (Radiant)

Gravitational Electrical

ENERGY CAN BE CHANGED FROM ONE FORM TO ANOTHER When energy is used, it's changed from one form to another. Let's look at an example of how energy changes.

Potential Energy

It is stored energy or the energy of place or position. 

Kinetic Energy

It is the energy of motion. It is the motion of waves, electrons, atoms,

Potential Energy 

Kinetic Energy

A rock on the top of a hill has energy. It is not moving—it has no kinetic energy. But it has energy because of its position on the hill. It has potential energy. If the rock begins to roll down the hill, its energy changes. The potential energy changes into kinetic energy as it rolls. When the rock stops

Purposes: To explore how potential energy is converted to kinetic energy. To explore how kinetic energy is converted into other forms of energy. Procedure: 1. Blow up the balloon to a diameter of about 10 cm and hold the end closed with your fingers. 2. Hold the balloon away from your face and let go of the end. Observe what happens. 3. Blow up the balloon to a diameter of about 15 cm, let it go, and observe. 4. Blow up the balloon to a diameter of about 20 cm, let it go, and observe. 1. What form of energy was in the blown up balloon? ________________________________________________________________________ 2. What happened to the air in the balloon when you let it go? ________________________________________________________________________ 3. What happened to the balloon when you let it go? ________________________________________________________________________ 4. How did the amount of air you put in the balloon affect its behavior when you let it go? ________________________________________________________________________ 5. Into what other forms of energy was the balloon’s energy converted when you let it go? ________________________________________________________________________ 6. How could you use the energy in a balloon to do work? ________________________________________________________________________

Diameter of Balloon Observation

Balloon – 10 cm diameter

Balloon – 15 cm diameter

Balloon – 20 cm diameter

 

OBJECTIVES: Participants will:

Correctly define and explain the concept of energy.

Correctly identify the two categories all energy forms can be classified into.

Name at least three forms of potential energy and three forms of kinetic energy.

Describe a situation in which energy is changed from one form to another. TN GUIDANCE CURRICULUM STANDARDS MEET: Science (4th Grade)GLE0407.10.1 Distinguish among heat, radiant, and chemical forms of energy. Science (5th Grade)GLE0507.10.1 Design and experiment to illustrate the difference between

potential and kinetic energy. Science (4th Grade)GLE0407.Inq.1 and Science (5th Grade)GLE0507.Inq.1

Explore different scientific phenomena by asking questions, making logical predictions, planning investigations, and recording data.

Science (4th Grade)GLE0407.Inq.2 and Science (5th Grade)GLE0507.Inq.2 Select and use appropriate tools and simple equipment to conduct and investigation.

ENERGY IN MOTION

1. Review the concept of energy with students. Energy is the power to change things, and it is the ability to do work.

2. Discuss potential versus kinetic energy. All forms of energy fall into these two categories. Potential energy is stored energy or the energy of place or position. Kinetic Energy is the energy of motion. Something has kinetic energy if waves, electrons, atoms, molecules, or substances move.

3. Give examples of potential and kinetic energy. a. Potential Energy

i. Stored Mechanical—The energy stored in objects or substance by the application of force.

1. Examples: Compressed metal springs and stretched rubber bands ii. Nuclear—The energy stored in the nucleus of an atom. It is the energy that

holds a nucleus together. 1. Example: Nucleus of a Uranium atom

iii. Chemical—The energy stored in the bonds of atoms and molecules. 1. Examples: Biomass, petroleum, natural gas, propane, and coal

iv. Gravitational—The energy of place or position. 1. Example: The water held in a reservoir behind a hydropower dam;

when water is released the turbines spin & produce electricity.

b. Kinetic Energy

i. Motion—The movement of objects or substances from one place to another. 1. Example: Wind

ii. Heat (Thermal)—The internal energy of substances. It is the vibration and movement of atoms and molecules within substances.

1. Example: Geothermal energy iii. Sound—The movement of energy through objects or substances in longitudinal

waves. iv. Light (Radiant)—The electromagnetic energy that travels in transverse waves.

1. Examples: Visible light, x-rays, gamma rays, and solar energy. v. Electrical—The movement of electrons.

1. Examples: Lightning and electricity 4. Explain to students that energy can be changed from one form to another. The example of the

rock falling is a good illustration of how potential energy (gravitational) is changed to kinetic energy (motion and sound). Another example that can be shared is a hydroelectric dam. The water held back in the reservoir has potential energy (gravitational). When the dam is open, the water flows (kinetic energy—motion) past turbines. The turbines move (kinetic energy—motion) and electricity (kinetic energy) is produced.

5. Perform the “Launch the Balloon” activity. The purpose of this activity is to explore how potential energy is converted to kinetic energy and how kinetic energy is converted to other forms of energy.

6. Have students record their observations of the balloon blown up to different diameters and released.

7. Answer conclusion questions. a. What form of energy was in the blown up balloon? Potential—Gravitational and Stored

Mechanical b. What happened to the air in the balloon when you let it go? It was released. c. What happened to the balloon when you let it go? The balloon shot across the room. d. How did the amount of air you put in the balloon affect its behavior when you let it go?

The more air in the balloon, the more energy, or faster it moves when it is released. Also, the sound is increased.

e. Into what other forms of energy was the balloon’s energy converted when you let it go? The potential (gravitational/stored mechanical) energy was converted into motion and sound.

f. How could you use the energy in a balloon to do work? You could use the balloons to lift and move objects (hot air balloons).

Friction is the resistance that a moving object meets when it is in contact with another object. It could be said to be a gripping force between two surfaces. Friction slows movement. It can also generate heat. The amount of friction there is will depend upon what the two, contacting surfaces are made off and how hard they are pressed together. What You Will Need For this Experiment: 1 ball or matchbox car, 1 grooved or flat ruler, 1 meter stick, textbooks Procedure:

1. One a tile floor, place one end of the ruler on a book as shown in the picture to make a slide.

2. Place the ball or matchbox car at the top of the ruler and let it go. Do not push it.

3. Measure how far it rolls from the end of the ruler and record in the chart below.

4. Repeat Steps 2-3 three times. 5. Repeat Steps 1-4 on a carpeted floor. Record your measurements in the

chart below.

Vs.

Distance the Ball Rolled Trial 1 Trial 2 Trial 3 Trial 4

Ball Roll on Tile Floor

Ball Roll on Carpeted Floor

Conclusions:

1. On which surface did the ball roll farther? _________________________ 2. Which surface applied more friction to the ball? ____________________ 3. Define FRICTION in your own words. _____________________________

_________________________________________________________ 4. What do you think would happen if you placed the ruler on two books?

_________________________________________________________ 5. What affect does the weight of the ball have? Would a heavier ball roll

farther? _______________________________________________

Fun with Friction

6. 7.

 

OBJECTIVES: Participants will:

Correctly define and explain the concept of friction.

Correctly identify the two factors that affect the amount of friction there will be.

Give at least one example of friction. TN GUIDANCE CURRICULUM STANDARDS MEET: Science (4th Grade)GLE0407.11.2 Design a simple investigation to demonstrate how friction

affects the movement of an object. Science (5th Grade)GLE0507.11.1 Design an investigation, collect data and draw conclusions

about the relationship among mass, force, and distance traveled.

Science (4th Grade)GLE0407.Inq.1 and Science (5th Grade)GLE0507.Inq.1 Explore different scientific phenomena by asking questions, making logical predictions, planning investigations, and recording data.

Science (4th Grade)GLE0407.Inq.2 and Science (5th Grade)GLE0507.Inq.2 Select and use appropriate tools and simple equipment to conduct and investigation.

ENERGY IN MOTION

1. Review the concept of friction with students. Friction is the resistance that a moving object meets when it is in contact with another object.

2. Discuss the two factors that affect the amount of friction there will be—how hard the two surfaces are pressed together and what the two contacting surfaces are made of.

3. Demonstrate examples of friction with students. a. When a ball flies through the air, it rubs against air molecules. The air molecules and

the molecules on the ball catch on each other. This contact is friction and it slows the movement of the ball down.

b. Have students rub their hands together. Your two hands contacting each other is an example of friction. Heat will be generated from this friction.

Fun with Friction

4. Conduct “Fun with Friction” experiment. This can be done as one big demonstration or the class can be broken up into smaller groups.

a. Have students create a book ramp as shown on page. b. Allow students to conduct experiment on a tile floor and then on a carpet floor. If

room doesn’t have carpet, you could bring a blanket to use as your surface. c. Roll the ball down the ramp and see how far the ball rolls on the carpet/tile. d. Repeat the trial 4 times on each surface.

5. Go over results from the experiment with students. a. On which surface did the ball roll farther? Tile Floor b. Which surface applied more friction to the ball? Carpet Floor c. Define FRICTION in your own words. It is when two surfaces come into contact with

each other and cause a gripping to occur between the two surfaces. d. What do you think would happen if you placed the ruler on two books? The ball

should go farther on both the carpet and tile. The ball at the top of two books has more potential energy than the ball on one book. However, the ball will always travel farther on tile than on the carpet due to less friction.

e. What affect does the weight of the ball have? Would a heavier ball roll farther? The heavier the ball, the more friction there is. Even though there is more friction with a heavier ball, the weight of the ball will cause the heavier ball to travel farther.

i. Demonstrate this concept to the class using a heavier ball.