Q: What are Earth's layers, from most dense to least dense?

Flexi Says: When Earth was entirely molten, gravity drew denser elements to the center and lighter elements rose to the surface. The separation of Earth into layers based on density is known as differentiation. The densest material moved to the center to create the planet’s dense metallic core. Materials that are intermediate in density became part of the mantle. Lighter materials accumulated at the surface of the mantle to become the earliest crust.