Materials Flashcards
Define matter
Anything which occupies space and has mass
Properties of solids
Definite shape, volume
Hard to compress
Don’t flow
Properties of liquids
No definite shape
Definite volume
Hard to compress
Do flow
Properties of gases
No definite shape
No definite volume
Easy to compress
Diffuse into all available space
Particle arrangement of liquids
more freedom of movement and can slide over each other
Move slowly
Particle arrangement in solids
Fixed position
Can vibrate
Strong force
Move slowly
Particle arrangement in gas
Farther apart than in liquid
Continuously moving around in all available space
Weak forces
Particles move quickly : this is why they diffuse
Why is it easier to compress gas?
There is more space between the particles : in liquid the particles are already very close to each other
Define diffusion
The spreading out of materials because of the movement of their particles
Melting point
The temperature at which a solid changes to a liquid
Measure the melting point of a solid
Seal one end of a melting point tube by holding it in a Bunsen burner
- benzoic acid in melting point tube
- melting point tube in aluminum melting point block
- aluminum melting point block on hot plate, heated
- note the temperature of when the benzoic acid changes to a colourless liquid from a digital thermometer connected to the melting point tube
Sublimation
Solids that change directly form a solid to a gas when heated
Evaporation
The changing of a liquid to a gas at the surface of the liquid
Boiling point
The temperature at which a liquid changes to a gas throughout the liquid
Condensation
The changing of a gas to a liquid : when a gas is cooled, the particles slow down