1. Density
One way of characterising materials is by their
density,

2. Density
 Density is a characteristic of
solids, liquids and gases;
◦ Solids are often very dense.
◦ Liquids are often less dense than solids.
◦ Gases have very low densities.
 The density of a substance is a
measure of how much mass they have
for a certain volume.

3. Calculating density
 The formula for calculating density is:
density, mass, m
volume,
V
m
V
 is the Greek letter rho and is usually
the symbol for density.

4. Formula triangle
If a question asks you
to write out the formula
for calculating
m density, do not use the
triangle – WRITE OUT
THE FORMULA!
x V

5. Measuring density
 The units for density depend on the
units used for mass and volume.
 If mass is measured in kilograms and
volume is measured in cubic
metres, the units for density are kg/m3.
 Density can also be measured in
g/cm3.

6. What can you remember?
DENSITY…..

7. Density
 solids, liquids
Density is a characteristic of solids,
and gases;
liquids and gases;
◦ Solids are often very dense.
very dense.
◦ Liquids are often less dense than solids.
less dense
◦ Gases have very low densities.
 The density of a substance is a
measure of how much mass they have
mass
volume.
for a certain volume.

8. Calculating density
 The formula for calculating density is:
density, mass, m
volume,
V
m
V
 is the Greek letter rho and is usually
Greek
the symbol for density.

9. Formula triangle
If a question asks you
to write out the formula
for calculating density,
m do not use the triangle
– WRITE OUT THE
FORMULA!
x V

10. Measuring density
 The units for density depend on the
volume.
units used for mass and volume.
mass
 If mass is measured in kilograms and
volume is measured in cubic
kg/m3.
metres, the units for density are kg/m3.
 Density can also be measuredg/cm3.
in
g/cm3.

11. mass, m
units are kg/m3 density,
volume, V
measure of matter
for volume
Solids
Gases DENSITY
very dense
low density Liquids
will not compress
can be compressed less dense
will not compress