Chemical Change Definition

Chemical vs. Physical Changes

Fun Facts

If you notice bubbles being formed, or a change in color or temperature, there is a good chance a chemical change has taken place.
Since chemical changes like burning wood make new substances, most of them cannot easily be undone.
A chemical change happens during digestion.

Why Do We Need To Know About Chemical Change

Learning about chemical changes helps us understand how new things are made and why this is important in many jobs. For example, in making medicines, putting chemicals together in new ways is using chemical changes.

This idea is also key in making fireworks, stopping things from rusting, and in cooking to make food. Knowing about chemical changes is important for people in these jobs to come up with new ideas and solve problems.

Frequently Asked Questions

What happens when Zoe stirs the very hot water with the spoon made from Gallium metal? What kind of change happens?

When Zoe stirs the hot water with the Gallium spoon, the metal melts. This is an example of a physical change because the Gallium changed forms, but it didn’t change into a new substance (it is still Gallium).

What kind of change happens when Dr. Jeff puts the gummy candy into a tube containing oxidizer? Why?

When Dr. Jeff drops the gummy candy into the tube containing oxidizer, the gummy candy bursts into flames producing smoke and carbon (new substances). Therefore, this is a chemical change.

What method did the team use to test what type of gas was produced in the reaction between the Mentos and soda?

Dr. Jeff, Izzy and Zoe used a balloon to collect some of the gas produced when soda and Mentos were combined. They then tested this gas to determine its properties. They concluded that it was carbon dioxide by observing that it extinguished candles.