Matter notes
1. What is matter?
Matter is anything that:
Has mass
Takes up space (volume)
Is made of particles
The particles in matter are constantly moving.
2. Solid
Properties:
Has a fixed shape
Has a fixed volume
Particles are very close together
Strong forces hold the particles together
Particles vibrate around fixed positions
Cannot flow
Almost impossible to compress
Examples: iron, ice, wood, salt
Key idea:
Solid particles have relatively low freedom of movement.
3. Liquid
Properties:
Has a fixed volume
Does not have a fixed shape
Takes the shape of its container
Particles are close together
Particles can move and slide past each other
Can flow
Very difficult to compress
Examples: water, mercury, oil
Key idea:
Liquid particles have more freedom to move than solid particles.
4. Gas
Properties:
Has no fixed shape
Has no fixed volume
Expands to fill its container
Particles are far apart
Particles move rapidly and randomly
Weak forces between particles
Easily compressed
Can flow
Examples: oxygen, carbon dioxide, helium
Key idea:
Gas particles have lots of space between them and lots of freedom to move.
5. Plasma
Plasma is sometimes called the fourth state of matter.
Forms when a gas gains a large amount of energy
Contains ions and free electrons
Conducts electricity
Can be affected by magnetic fields
Found naturally in stars and lightning
Examples: Sun, lightning, auroras
6. Changes of State
Change
Process
Solid → Liquid
Melting
Liquid → Solid
Freezing
Liquid → Gas
Evaporation / Boiling
Gas → Liquid
Condensation
Solid → Gas
Sublimation
Gas → Solid
Deposition
These are physical changes because the substance itself does not become a different substance.
7. Heating and Cooling
When a substance is heated:
Its particles gain kinetic energy
They generally move faster
The substance may change state
When a substance is cooled:
Particles lose kinetic energy
They generally move more slowly
The substance may change state
Example:
Ice → Water → Steam
Solid → Liquid → Gas
As energy is added, the particles become increasingly free to move.