Density is a measure of the amount of mass in a given amount of space. If you have two rocks of the same size, but one is heavier than the other; then it could be assumed that one is more dense than the other.
Mathematically stated: Density = Mass
Made-up Example : What is the density of a sample of pure iron if it's mass is 34 grams, and a volume of 4 mL?
Convert 4mL to L:
Density Iron sample=