: A material's density is determined by the mass of its individual atoms and how closely those atoms are arranged. Common Examples Density (Approx.) Air 1.29 kg/m³ Ice 917 kg/m³ Water 1,000 kg/m³ Lead 11,340 kg/m³ 💡 Pro Tip: The Density Triangle To easily rearrange the formula for different calculations: To find Mass : Density To find Volume : Mass ÷divided by To find Density : Mass ÷divided by Expert Perspectives

: Think of it as how "tightly packed" the matter is. For example, a cubic centimeter of bricks is much denser (1.6 g/cm³) than a cubic centimeter of feathers (0.0025 g/cm³). Key Characteristics

: Since density is unique to each substance at a given temperature, it is often used to identify unknown materials.

: An object will float in a fluid if its density is lower than the fluid's and sink if it is higher. Water has a defined density of 1.0 g/cm³.

“Think of a fruit basket... The total weight of the fruits is the same, but the basket's size determines how densely packed they are.” Teach Spectacular Science quick density review

Users often find the relationship between size and weight the most intuitive way to grasp the concept.

“The simple answer is how heavy something is for its size. If something seems very heavy for its size, we say it is more dense.” Purdue University