The density of Earth changes dramatically with depth, increasing from the relatively low density of the crust to the extremely high density of the core. Here's a breakdown of how density changes through Earth's layers:

1. Crust:

* Density: 2.7 to 3.0 g/cm³

* The crust is the outermost layer, composed of relatively light elements like silicon, oxygen, and aluminum.

* It's the least dense layer, with a density similar to granite.

2. Mantle:

* Density: 3.3 to 5.5 g/cm³

* The mantle makes up the bulk of Earth's volume, extending from the crust to the outer core.

* It's composed primarily of silicate minerals, and its density increases with depth due to:

* Pressure: The immense pressure from overlying layers compresses the mantle material, making it denser.

* Composition: The lower mantle contains heavier elements like iron and magnesium than the upper mantle.

3. Outer Core:

* Density: 9.9 to 12.2 g/cm³

* This layer is composed primarily of molten iron and nickel.

* It's significantly denser than the mantle due to the presence of heavier metals and the high pressure.

4. Inner Core:

* Density: 12.6 to 13.0 g/cm³

* The innermost layer is a solid ball of iron and nickel, despite the extreme heat.

* The immense pressure at the center of Earth is so great that it overcomes the melting point of iron, forcing it to remain solid.

Summary:

The density of Earth increases dramatically as you move from the crust to the core. This is due to a combination of factors:

* Pressure: The deeper you go, the greater the pressure, which compresses the material and increases its density.

* Composition: The core is composed of heavier elements (iron and nickel) than the crust and mantle.

* State of matter: The outer core is liquid, while the inner core is solid, which also affects density.

This density variation is crucial for understanding Earth's structure, how it formed, and how it continues to evolve.