Physical ScienceMatter

Objectives

• By the end of this lesson, you should be able to• Detail the different types of matter• Describe the difference between physical properties and chemical

properties• Provide examples of physical and chemical properties• Calculate the density of an object• Describe the difference between physical changes and chemical

changes

Standards

• SPS2.• Students will explore the nature of matter, its classifications, and its

system for naming types of matter.

You know it when you see it, unless it’s air• Chemistry is primarily a study of matter and how different types of

matter interact

• But what is matter?

• At its simplest definition, matter is anything that has mass and takes up space• You could think of it as anything having weight and volume

Breaking it down

• All matter is made up of one or more elements

• An element is the basic type of matter

• All elements are made up of one or more of the same kind of atom

• Atoms are the smallest part of an element, which is still an element

“What’s it going to be”

• If elements are put together but don’t actually combine, it is known as a mixture

• If elements are put together and DO combine, then it is called a molecule

• If different elements are put together and combine, then it is called a compound

Two types of properties

• There are general two describe substances

• Physical properties• Physical characteristics

• Chemical properties• How they react when combined with other substances

Physical Properties

• Color• Odor• Texture• Taste• Melting point• Boiling Point• Physical state at room

temperature

• Luster (how shiny it is)• Density• Malleability (ability to be

shaped)• Ductility (ability to be stretched• Hardness (ability to be

scratched)• Conductivity• Magnetism

NOTE: These are the most common, but not all of them

Density

• Which is heavier: a pound of feathers or a pound of lead?• The answer is of course – they are the same weight• The difference is how compact, or how dense each is

• Density = mass/volume• D = m/v• Usually, mass is in grams (g), volume is in milliliters (mL) or cubic centimeters

(cm3), and density is in either grams per mL (g/mL) or grams per cm3 (g/cm3)

Density triangle

m

D v

The way you use triangles like this is by covering up the variable you are trying to find. The triangle will then show you what operation to perform

If you must go this way, then divide

If you must go this way, then multiply

Chemical Properties

• Two most common

• Flammability: how easy it is to burn

• Reactivity: How quickly and energetically it reacts with other substances

Physical Changes

• Most students know that water can be liquid, solid (ie. Ice), or gas (ie water vapor)• Since it stays water, you should realize that melting, freezing, boiling,

and condensing are all physical changes• In a physical change, the substance remains that substance• Other examples of physical changes include:• Dissolving• Being broken into smaller pieces

Chemical Changes

• When a chemical change occurs, the substance has CHANGED into another substance• Indications of a chemical change include changes in physical

properties

• Examples include:• A shiny copper penny may turn green• An iron pipe could turn a reddish-brown color• Something that was a solid at room temperature is now a liquid

“You can’t make an omelet with breaking a few eggs”• Imagine pouring ingredients into a mixing bowl: milk, eggs, and sugar• Even with mixing them, they still remain milk, eggs, and sugar• Mixing is a physical change

• Now, put them in the oven• The milk and eggs will change from a liquid to a solid• All will change colors• Baking causes chemical changes to occur