Physical Properties

The physical properties of a substance describe things such as:

• ​Its appearance

• The temperatures at which it melts, freezes and boils

• Its hardness (how easily it is to scratch the material).

​Density is one of the physical properties of a substance.

What is density?

Density is a measure of how much matter is packed into a space.

Density depends on how heavy a substance is, but it is not the same as its weight or mass. For example, 1 kilogram of lead always weighs exactly the same as 1 kilogram of polystyrene, which weighs as much as 1 kilogram of feathers.

​Same mass but take up different amount of space.

How to talk about density

Density is the mass of something compared to its volume. Therefore, we talk about density in terms of grams per cubic centimetre (g/cm³).