One of the physical properties of a substance, being how much matter is packed into a space and how compact something is.
Sinking and Floating
Density determines whatsinks and what floats. The more dense objects sink while the less dense float, which is why some rocks, such as pumice, drift on top of the ocean whereas others sink, like granite.
Expansion
When particles move apart from heat.
Contraction
When particles move closer due to colder temperatures.
Pressure
The amount of force from the particles colliding with wall of a substance in a certain area.
Mixing
When a solute dissolves, the solvent particles surround the solute particles, carrying the solute away.
Diffusion
The naturalmovement of fluids from an area of highconcentration to an area of low concentration, particularly with regards to gasses.
Comparing Densities
Density is generally measured in g/cm^3.
Density and Packing
Particles in a solid are packed more closely than they are of a liquid, meaning most solids are denser than their liquid counterpart of the same material. When heated, particles spread out.
Floating and Sinking
Density determines how different substances arrange themselves when mixed together. For example, denser substances will sink.
