Changes in Matter

Matter is anything that takes up space and has mass. Everything around you—water, air, rocks, and even your favorite snack—is made of matter. Matter can be found in three main forms called states of matter: solid, liquid, and gas. But did you know that matter can change from one form to another?

There are two main ways that matter can change: physical changes and chemical changes. A physical change happens when matter changes its size, shape, or state, but it is still the same substance. For example, when ice melts into water, it is still water. Cutting paper into smaller pieces is also a physical change, because the paper is still paper. Physical changes are often easy to reverse.

A chemical change happens when matter forms a new substance with different properties. This means the change cannot be easily undone. For example, when you bake a cake, the ingredients mix and react to make something new. Burning wood is another chemical change. After the wood burns, it turns into ash and cannot become wood again. Signs of a chemical change include a color change, heat or light being given off, or the formation of gas bubbles.

Scientists use the word property to describe how matter looks, feels, or behaves. Properties can include color, texture, and whether something is hard or soft. Changing the state of matter, like boiling water to make steam, is a physical change because water is still water, just in a different state.

Understanding how matter changes helps us in everyday life. We use physical changes when we freeze juice to make popsicles. We use chemical changes when we cook food, like baking bread or frying eggs.

Interesting Fact: The Statue of Liberty’s green color is a result of a chemical change called oxidation, which happened when the copper surface reacted with air and water over many years!