P3 : Density

Question 1

Solids

Answer 1

. Particles are very close together
. Particles arranged in a a regular pattern
. Particles vibrate but don’t move from place to place

Question 2

Liquids

Answer 2

. Particles still close together
. Not arranged in a regular pattern
. Particles can move around each other

Question 3

Gas

Answer 3

. Particles are far apart
. Particles are not arranged in any pattern
. Particles are moving very rapidly

Question 4

Density

Answer 4

The density of a material tells us the mass for a given volume
Solids usually have high density because the particles are close together and there is a lot of mass in the volume
Liquids usually have high density because particles are still close together so there is a lot of mass in the volume
Gases have a low density because the particles are far apart and only have a small mass for their volume

Question 5

How do you calculate density

Answer 5

ρ = m / v
ρ = Density (kg/m3)
m = mass (kg)
v = Volume (m3)

Question 6

Polystyrene

Answer 6

Polystyrene is a solid but has a low density. Polystyrene has a very open structure and is full of air spaces, it has a small mass for it’s volume