Changes in Matter - I Can Change It Myself!
Matter can change!
As you discovered, matter can change. There are two types of changes that can occur to matter; physical changes and chemical changes. What does that mean when a physical or chemical change occurs? If you break a candle, some pieces of the candle will end up on one side of the wick and the rest of them will end up on the other side. This would be a physical change.
What happens when a candle burns? After lighting the candle, fire begins to burn the wick. After a time, the wax seems to disappear. Where does it go? The answer is "up in smoke!" The burning wax appears to change from a solid to a gas. The wax burns to form two different materials, which demonstrates a chemical change. All of the matter that made the candle is still somewhere, but it is not all still part of the candle. The matter was not destroyed. That is what scientists mean when they say matter cannot be created or destroyed by ordinary means. What about extraordinary means? That's a whole other story.
You're the scientist!
One very important thing that scientists do is to make observations. With the help of an adult, light a candle and watch it burn. Write down what you observe as the candle burns.
More fun with Chemical and Physical Changes.
We know that with chemical changes the following things can happen:
- Color change
- Heat is given off
- Heat is used
- New material is formed
- Sometimes in chemical reaction a gas is also given off.
- Antacid tablets such as Alka Seltzer®
This activity will be done by yourself or with a partner.
- Crush one tablet into a powder
- Put the powder onto the spoon.
- Have one partner put powder into cup A and the other partner puts a tablet into cup B.
- Put in several drops of vinegar. Make sure you put the same amount of vinegar in each cup.
Which tablet dissolves first? Why?
Congratulations, you have just performed a chemical reaction.
In this experiment you learned a bit more about chemical reactions and how to speed them up – by making the surface area of the reactant smaller.