Physical Change…Chemical Change

The three states of matter are SOLID, LIQUID, and GAS. You know that matter can often change its state. An example of this is water freezing. Sometimes, though, matter changes into an entirely different substance and can’t be changed back again. These two types of changes are called physical and chemical changes.

Physical change

• Matter changes the state it is in
• The change is not permanent (it can be undone)
• No chemical changes take place in the matter

 

Chemical change

• Matter changes from one substance to another
• The change cannot be reversed

Let’s see how this works

 

 

PHYSICAL CHANGES vs. CHEMICAL CHANGES

Here is what you need:

• Modeling clay
• Water
• Stove
• Pan with a lid
• 2 small containers
• Balloon
• Eggs (2)
• Ice cream
• Matches
• Fire-proof container
• Piece of paper

 

 

Here is what you do:

NOTE: This experiment is actually a series of experiments. Each one shows a physical or chemical change. Do you know which ones are which?

• Roll the clay into a ball
• Flatten it
• Make a clay animal figure
• Flatten it or roll it into a ball

Is this a physical or chemical change?

 

• Pour 1 cup of water in a pan, put it on the stove, turn on the heat and bring to a boil. When it boils, observe the steam coming up from the pan. Turn the stove off and cover the pan with the lid. Let it set for a couple of minutes and remove the lid. What changes have taken place?
• Pour 1 cup of water into a small container and place it in the freezer for 4 to 6 hours. What changes have taken place?
• Pour 1 cup of water into a small container and set it on the table. What changes have taken place?

Is this a physical or chemical change?

 

• Hold the uninflated balloon in your hand. What words would you use to describe it?
• Blow the balloon up but do not tie it off. How is the balloon different than it was before you blew it up?
• Let the balloon go. Does it look the same as it did before you blew it up?

Is this a physical or chemical change?

 

• Hard-boil and egg using the pan and water
• Break the other egg open into a small container (raw)
• After the hardboiled egg has cooled, remove the shell and cut the egg open

Is this a physical or chemical change?

 

• Put some ice cream in a dish
• Eat one or two bites then leave the dish set on the table for 30 to 45 minutes
• What has happened to the ice cream?
• Put the ice cream back into the freezer—in the bowl
• Check it after 10 to 15 minutes

Is this a physical or chemical change?

 

• Put a piece of paper into the fireproof container
• Using a match, light the paper on fire and let it burn completely up
• What do you have left?

Is this a physical or chemical change?