The earth's innermost layer is known as the core when considering properties, but is broken into 2 layers, outer core and inner core, when discussing properties.

chemical... physical

Explanation:

The layers of the Earth are divided into two manners, depending on their physical and chemical properties. The division in accordance to the physical properties is inner core, outer core, mesosphere, astenosphere, and lithosphere. The chemical division of the layers is simpler, core, mantle, and crust. Whichever division we use there is obvious differences between the layers. In general we can say that the deeper layers are denser, while the outer layers are less dense. The pressure and temperature are higher in the deeper layers, while they are smaller in the outer layers. The composition of them differs, with the deeper layers having heavier elements, while the outer layers having lighter elements.