1.1 understand the arrangement, movement and energy of the particles in each of the three states of matter: solid, liquid and gas

SOLIDS:

- In solids, there are very strong forces of attraction between all of the particles - this is what holds the very tightly together. The particles are in a fixed position which is why the particles form the lattice arrangement.
- As the particles are tightly packed, the particles cannot move hence keeping the same shape and the same volume.
- In solids, the particles vibrate (although you can't see it) and when the solid starts to heat up the particles vibrate more which causes the object to expand. Like a metal bridge, sometimes the joints of the bolts become loose since in the day the steel heats up and expands then during the night it cools and reverts back to its normal position.

LIQUIDS:

- In liquids, there is a weak force of attraction between the particles. The particles are randomly arranged and are therefore free to move around each other (However don't be confused with gases since liquids tend to stick near each other).
- Liquids have the same volume but don't stick to the same shape therefore will try to fit its container.
- In liquids, the particles never stop moving and they move randomly. Just like solids when they are heated the particles vibrate more (or move faster). Hence expanding.

GASES:

- In gases, there is a VERY weak force of attraction which allows them to move freely and spread out far. They only travel in straight lines.
- Gases never keep the same volume or shape and so will always fit any container.
- In gases, the particles constantly move (always in a random motion). As the gas gets heated, the particles move faster. When heated the gases either expand / or their pressure increases.