Lesson 1 β Activity 1: Describing Matter
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Lesson 1 β Activity 1: Describing Matter
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Remember that matter is anything that has mass and takes up space. Matter is everywhere. You are surrounded by it. You are also made up of it. The air we breathe, the food we eat, the water we drink, and the ground we walk on are all made up of matter.
Matter can take on a variety of different forms, which all have a variety of different properties. In this activity, you will learn how matter can be described.
Scientists have investigated matter for hundreds of years and have developed a theory to help them describe and explain the characteristics of matter.
They have called this theory the particle theory of matter.
The particle theory of matter says the following:
- All matter is made up of very tiny particles.
- All particles in a pure substance are the same. For example, distilled water is only one colour because all of the particles that make it up look exactly the same.
- There are spaces between particles. The image below shows that the distance between particles is different for solids, liquids, and gases.
Created with BioRender.com
- Particles are always moving. As particles gain energy, they move faster.
- The particles in a substance are attracted to each other.
Click on the Play button to watch a video that further explains the particle theory of matter.
States of Matter
Matter
exists in three basic states: solid, liquid, and gas. The particle theory of matter can be used to explain these three states of matter.
In
solids, particles are packed tightly together and cannot move very
much. This means that a solid will keep its shape and not flow.
In liquids, particles are touching but can move past each other. This explains why liquids can take the shape of their container and flow easily.
Yelod - Wikimedia Commons * Yelod - Wikipedia (En) * ΧΧΧΧ - ΧΧΧ§ΧΧ€ΧΧΧ ΧΧ’ΧΧ¨ΧΧͺ, CC BY-SA 3.0
Particles in a gas are far apart and move quickly. Particles in a gas will keep moving away from each other until stopped by the walls of a container.
There is also a fourth state of matter that exists only at extremely high temperatures. This is called the plasma state. The surface of the Sun is so hot that most of the substances there exist as plasma.
The particle theory of matter says the following:
- All matter is made up of very tiny particles.
- All particles in a pure substance are the same. For example, distilled water is only one colour because all of the particles that make it up look exactly the same.
- There are spaces between particles. The image below shows that the distance between particles is different for solids, liquids, and gases.
Created with BioRender.com
- Particles are always moving. As particles gain energy, they move faster.
- The particles in a substance are attracted to each other.
Click on the Play button to watch a video that further explains the particle theory of matter.
States of Matter
Matter
exists in three basic states: solid, liquid, and gas. The particle theory of matter can be used to explain these three states of matter.
In
solids, particles are packed tightly together and cannot move very
much. This means that a solid will keep its shape and not flow.
In liquids, particles are touching but can move past each other. This explains why liquids can take the shape of their container and flow easily.
Yelod - Wikimedia Commons * Yelod - Wikipedia (En) * ΧΧΧΧ - ΧΧΧ§ΧΧ€ΧΧΧ ΧΧ’ΧΧ¨ΧΧͺ, CC BY-SA 3.0
Particles in a gas are far apart and move quickly. Particles in a gas will keep moving away from each other until stopped by the walls of a container.
There is also a fourth state of matter that exists only at extremely high temperatures. This is called the plasma state. The surface of the Sun is so hot that most of the substances there exist as plasma.
Self-Check
Try This!
Try the questions below on your own first and then click on the tab to check your answers!
1. _________ is anything that takes up space and has a mass.
2. In what state are the molecules packed closely together in rows and columns, like a brick wall?
- liquid
- gas
- solid
3. In what state are the molecules moving so fast they bounce out of the container and into the air?
- liquid
- gas
- solid
4. As particles gain energy, they:
- move slower
- move faster
- stay the same
1. matter
2. solid
3. gas
4. move faster
Matter changes state when special forces act on it. For instance, if you place liquid water in the freezer, it becomes solid ice. The special force that worked on the matter is temperature. Another special force is pressure.
The image below shows further information of how matter changes state.
Solids change to liquids (melting) when heat energy is added or pressure is reduced.
Phase changes of matter. [Photograph]. Retrieved from Encyclopædia Britannica ImageQuest.
https://quest.eb.com/search/309_1156147/1/309_1156147/cite
Gases change to liquids (condensation) when heat energy is taken away (cooling) or pressure is increased.
Liquids change to gases (evaporation) when heat energy is added or pressure is reduced.
Liquids change to solids (freezing) when heat energy is taken away (cooling) or pressure is increased.
Experiment!
Change water vapour into a liquid. Fill a glass with ice cubes and cold water. Place it on your counter for a few minutes.
The
water droplets on the outside of the glass indicate that you have
decreased the temperature around the outside of the glass enough to
change water vapour in the air to water β you changed the state of
matter from gas to liquid!
Here is a list of key terms that are used when describing states of matter and physical changes. These terms are used to describe water, gold, plastic, or any other matter.
- melting point β the temperature at which a solid changes to a liquid
- freezing point β the temperature at which a liquid changes to a solid
- boiling point β the temperature at which a liquid changes to a gas
Matter changes state when special forces act on it. For instance, if you place liquid water in the freezer, it becomes solid ice. The special force that worked on the matter is temperature. Another special force is pressure.
The image below shows further information of how matter changes state.
The image below shows further information of how matter changes state.
Solids change to liquids (melting) when heat energy is added or pressure is reduced.
Phase changes of matter. [Photograph]. Retrieved from Encyclopædia Britannica ImageQuest.
https://quest.eb.com/search/309_1156147/1/309_1156147/cite
https://quest.eb.com/search/309_1156147/1/309_1156147/cite
Gases change to liquids (condensation) when heat energy is taken away (cooling) or pressure is increased.
Liquids change to gases (evaporation) when heat energy is added or pressure is reduced.
Experiment!
Change water vapour into a liquid. Fill a glass with ice cubes and cold water. Place it on your counter for a few minutes.
The water droplets on the outside of the glass indicate that you have decreased the temperature around the outside of the glass enough to change water vapour in the air to water β you changed the state of matter from gas to liquid!
Here is a list of key terms that are used when describing states of matter and physical changes. These terms are used to describe water, gold, plastic, or any other matter.
- melting point β the temperature at which a solid changes to a liquid
- freezing point β the temperature at which a liquid changes to a solid
- boiling point β the temperature at which a liquid changes to a gas