Calculating Density of a Rock

What is the density of the rock?

A rock dropped in a graduated cylinder raises the level of water from 30mL to 45mL. The rock has a mass of 60g. What is the density of the rock?

Density of the Rock

The density of the rock can be calculated using the formula:

Density = Mass ÷ Volume

Density is an intensive property, meaning it does not depend on the quantity of the substance. In this case, the mass of the rock is 60g and the volume (difference in water level before and after adding the rock) is 45mL - 30mL = 15mL.

Substitute the values into the formula:

Density = 60g ÷ 15mL = 4g/mL

Therefore, the density of the rock is 4g/mL.

Understanding Density

Density is a measure of how much mass is contained in a given volume. It tells us about the compactness of a substance, or in simpler terms, how tightly packed the particles are within the material.

Objects with higher density are more compact and heavier for their size. For example, if an object is denser than water, it will sink in water because the water cannot support its weight due to its lower density.

Mathematically, the formula to calculate density is:

Density = Mass ÷ Volume

In the case of our rock, we determined that its density is 4g/mL. This means that for every milliliter of volume, the rock has 4 grams of mass packed within it.

Understanding density is essential in various scientific fields such as physics, chemistry, and geology. It helps us classify materials, predict their behavior under certain conditions, and make comparisons between different substances.