Physical Change Definition

Chemical vs. Physical Changes

Fun Facts

Combining milk and cereal for breakfast is a physical change.
Mixing Mentos with soda is a physical change because no new substance is made.
It is usually easy to reverse a physical change, like dissolving sugar in water then evaporating the water to leave the sugar crystals behind.

Why Do We Need To Know About Physical Change

Learning about physical changes helps us know why different materials act the way they do and why changing them is important for lots of jobs. For example, knowing how a metal like Gallium can melt and solidify without turning into a different substance helps in making things from everyday items to high-tech gadgets.

This knowledge isn’t just for scientists but for everyone. When you whip egg whites to make them fluffy for cooking, that’s a physical change. Also, in things like cleaning water or designing eco-friendly projects, using physical changes is key. Understanding physical changes is useful for many reasons.

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.