Basic Chemistry/States of matter
Matter exists in four different forms - solid, liquid, gas, and plasma. These are the four states of matter. You can recognize each state because they have different properties. A property of a material describes how it behaves. This behavior is not observable at the chemical level due to microscopic sized particles. We can observe how many H2O particles behave when we open a faucet, releasing water, which is a lot of H2O particles in their liquid state. Of course we can observe other states of H2O particle groupings, at low temperatures they freeze, demonstrating a solid property. At high temperatures they form a gas called steam. Behavior is how something responds when placed in a container, when it is squeezed, or released.
States of matter
|Volume||has definite volume||has definite volume||has no definite volume-always fills the container they are in|
|Shape||have a definite shape||match the shape of the container||become the same shape as the container|
|Density||have a high density||have a high density||have a low density|
|Compressibility||not easily squashed||not easily squashed||easily squashed|
|Flow||don't flow||flow easily||flow easily|
- All materials are made up of particles.
- The particles that are in a substance (material) stay the same whatever state the substance is in. The only thing that changes is the arrangement of the particles and the energy they have.
- Whichever state the substance is in depends on how strongly the particles stick together. And how well the particles stick together depends on:
- the material
- the temperature
- the pressure.
- This is particle theory, and it explains all the different properties of solids, liquids and gases.
- PARTICLES ARE HELD VERY CLOSE TOGETHER AND HAVE LIMITED MOVEMENT SPACE
- They are held tightly together by strong forces of attraction.
- They are held in fixed positions but they do vibrate.
- Because the particles don't move, solids have a definite shape and volume, and can't flow.
- Because the particles are already packed closely together, solids can't easily be compressed.
- Because there are lots of particles in a small volume, solids are dense.
- Powdered solids cannot take the shape of their container.
- PARTICLES ARE CLOSE TOGETHER BUT CAN MOVE
- Particles are still touching and held very by strong forces of attraction.
- But they are free to move past each other.
- Because the particles can move, liquids don't have a definite shape, and they can flow.
- Because the particles are still packed close together, liquids can't easily be compressed and keep the same volume.
- Because there are lots of particles in a small volume, liquids have almost the same density as when they were solid, some, like water are actually more dense than their solid, but most are very slightly less dense.
- PARTICLES ARE FAR APART
- Particles are far apart from each other because there are very weak forces of attraction between them.
- They move fast in all directions.
- Because of this, gases don't have a definite shape or volume and fill any container.
- Because there is lots of free space between particles, gases can easily be compressed.
- Because there aren't many particles in a large volume, gases have very low densities typically 1000 times less than in their condensed state as solid or liquid at atmospheric temperature and pressure.