Chemistry - C2b - Types Of Matter Flashcards
what are the 3 states of matter ?
- solid
- liquid
- gas
what does the state the material is in depend on ?
how strong the forces of attraction are between the particles of the material
what is the strength of forces between particles determined by ?
- the material (the structure of the substance and the type of bonds holding the particles together)
- the temperature
- the pressure
describe the properties of solids
- strong forces of attraction between particles, which holds particles together in fixed positions to form a regular lattice arrangement
- keep a definite shape and volume
- don’t move from their positions
- don’t flow like liquids
- vibrate about their positions
- vibrate more when temperature increases - expand slightly when heated
describe the properties of liquids
- weak forces of attraction between particles
- randomly arranged
- free to move past each other, but tend to stick closely together
- have a definite volume, not a definite shape
- particles constantly moving with random motion
- hotter the particles get, the faster they move
- expand slightly when heated
describe the properties of gases
- very weak forces of attraction
- free to move
- move randomly
- travel in straight lines until they collide
- particles are very far apart
- don’t keep a definite shape or volume
- will always fill a container
- the hotter a gas gets, the faster they get, the more collisions made - increase in pressure, if container isn’t shut volume increases
what are the limitations of the particle theory ?
- don’t show the forces between the particles
- the size of the particles and the distances between them isn’t always accurate
- in reality, they aren’t spheres, solid or inelastic - they’re atoms, ions or molecules
what are the state symbols for :
solid
liquid
gas
aqueous
- s
- l
- g
- aq
what type of change is a change of state ?
a physical change
what is solid changing to liquid called ?
melting
what is melting ?
a solid is heated, so gains more energy, which makes the particles in a solid vibrate more which weakens the forces that hold the solid together. At the melting point the particles have enough energy to break from their positions
what is a liquid changing to a gas called ?
boiling
what is boiling ?
a liquid is heated, so the particles gain more energy which makes them move faster, which weakens the attractive forces holding the liquid together. At the boiling point, the particles have enough energy to overcome the forces between them
what is a gas changing to a liquid called ?
condensation
what is condensation ?
as a gas cools, particles don’t have enough energy to overcome the forces of attraction between them, so at the boiling point the forces between the gas particles are strong enough that the gas becomes a liquid