What is the layer of the earth with the lightest elements?

The layer of the Earth with the lightest elements is the crust. Composed primarily of silicate minerals, it contains lighter elements such as oxygen, silicon, aluminum, and potassium. The continental crust is generally thicker and less dense than the oceanic crust, which is primarily made up of basaltic rock. Overall, the crust sits above the denser mantle and core layers.