States of Matter Lesson: How Materials Exist and Change

Lesson Overview

• What Are the States of Matter?
• Solids: Matter That Holds Its Shape
• Liquids: Matter That Flows and Adapts
• Gases: Matter That Fills the Space
• Plasma: The Electrified State of Matter
• Bose-Einstein Condensate (BEC): The Coldest State
• How Matter Changes State: Phase Changes
• Properties of Each State of Matter
• Can You Compress Matter?
• How Does Matter Behave in Containers?
• Examples of Matter and Changes
• Special States of Matter (Plasma and BEC)

Everything in the world is made of matter. Matter is anything that takes up space and has mass. From the air we breathe to the food we eat, matter exists all around us. But matter doesn't always look or act the same-it can be solid, liquid, gas, or even exist in more unusual forms like plasma and Bose-Einstein Condensate.

In this lesson, you will learn about the five main states of matter, how they behave, how they change, and where we can find them in everyday life.

What Are the States of Matter?

There are five states of matter that scientists recognize today:

Let's explore each state in more detail.

Solids: Matter That Holds Its Shape

A solid has:

• A fixed shape
  
• A fixed volume
  
• Tightly packed particles that vibrate in place
  

Solids do not change shape unless they are broken, cut, or melted. Examples include:

• A pencil
  
• Ice
  
• A brick
  

Solids do not take the shape of their container, unlike liquids or gases.

Take This Quiz:

Test on States of Matter! Chemistry Quiz

Liquids: Matter That Flows and Adapts

A liquid has:

• A fixed volume
  
• No fixed shape
  

Liquid particles are loosely packed, allowing them to flow and move. They take the shape of the container but don't fill it completely.

Examples of liquids:

• Water
  
• Oil
  
• Juice
  

Liquids are not easily compressed because the particles are still fairly close together.

Gases: Matter That Fills the Space

A gas has:

• No fixed shape
  
• No fixed volume
  

Gas particles are spread far apart and move freely. This allows gases to:

• Fill the entire volume of their container
  
• Be easily compressed
  
• Expand to occupy any available space
  

Examples:

• Air
  
• Steam
  
• Helium in a balloon
  

Because of their loose particle arrangement, gases can change size and shape very easily.

Plasma: The Electrified State of Matter

Plasma is a state where gases become ionized-meaning the atoms lose or gain electrons and turn into charged particles.

Plasma:

• Conducts electricity
  
• Produces light
  
• Exists at very high temperatures
  

Where can you find plasma?

• In stars, including the sun
  
• Neon signs
  
• Lightning bolts
  

Plasma is called the fourth state of matter and is different from regular gases due to its electrical properties.

Bose-Einstein Condensate (BEC): The Coldest State

Bose-Einstein Condensate (BEC) is a state of matter that forms at temperatures close to absolute zero (−273.15°C or 0 Kelvin). At this point:

• Atoms slow down almost completely
  
• Particles behave as if they are one single unit
  
• It can only be created in special labs
  

BECs help scientists study quantum mechanics (how tiny particles behave).

How Matter Changes State: Phase Changes

Matter can change from one state to another. These changes are called phase changes and happen when you add or remove heat.

Example:

• Melting: Ice cube turning into water
  
• Evaporation: Water drying up in the sun
  
• Condensation: Water droplets forming on a cold glass
  

Properties of Each State of Matter

Let's compare how solids, liquids, and gases behave.

These properties help us recognize and describe the different states in real-life situations.

Take This Quiz:

Test quiz on different states of matter 

Can You Compress Matter?

Compression means reducing the volume of something by applying pressure. Here's how it works for each state:

• Solids: Cannot be compressed. Particles are already close together.
  
• Liquids: Very hard to compress. Particles are still close but can move.
  
• Gases: Easily compressed. There is lots of empty space between particles.
  

That's why air in a balloon can be squeezed, but water in a jar cannot.

How Does Matter Behave in Containers?

Each state of matter acts differently when placed in a container:

For example, if you put air or steam in a large bottle, it spreads to fill every part of it. But a rock will stay the same size and shape no matter what container it's in.

Examples of Matter and Changes

Let's look at some everyday examples of matter and how it changes:

Recognizing these changes helps you see science in action all around you.

Special States of Matter (Plasma and BEC)

Although solids, liquids, and gases are the most familiar, the other two states-Plasma and BEC-are important in science and technology.

Scientists study these states to understand energy, light, and atoms better. Even though you don't see them every day, they are part of the amazing world of matter.