It’s a busy day at the state fair as you and your classmates navigate your way through the crowd. While you follow your teacher, you can’t help but notice the many sights and sounds that surround you. Eventually, you fall behind the group as you spot the most amazing ride you have ever seen. You inspect it from one end to the other.How will you describe it to the group when you catch up to them? What features will you use in your description?
Perhaps you will mention that the ride is large, blue, and made of wood. These features are all physical properties, or characteristics, of the ride.A physical property is a characteristic that you can observe without changing or trying to change the composition of the substance. How something looks, smells, sounds, or tastes are all examples of physical properties. In Figure 1 you can describe and differentiate all types of matter by observing their properties.
Some properties of matter cannot be identified just by looking at a sample. For example, nothing happens if you look at thematches in the first picture. But if someone strikes the matches on a hard, rough surface they will burn, as shown in the second picture. The ability to burn is a chemical property. A chemical property is a characteristic that cannot be observed without altering the substance.As you can see in the last picture, the matches are permanently changed after they are burned. Therefore this property can be observed only by changing the composition of the match.Another way to define a chemical property, then, is the ability of a substance to undergo a change that alters its identity. You will learn more about changes in matter in the following section.
Source: Glencoe Science-The Nature of Matter-SE_0078617650