Final answer:
Density is a physical property that measures the amount of matter in a substance. It is the ratio of mass to volume and does not depend on the size of the sample.
Step-by-step explanation:
Density is a physical property that measures how much matter is present in a substance. It is the ratio of the substance's mass to its volume. Density is an intensive property, meaning it does not depend on the size of the sample. For example, a sample of pure aluminum will always have a density of 2.70 g/cm³ at 20°C, regardless of its mass or volume.