question:
What is the smallest unit of an element that still has the properties of that element?

answer:
an atom

question:
Which action forms a different chemical substance?

answer:
burning a piece of wood

question:
Rocks that contain fragments of bones, shells, and plant remains are most likely

answer:
sedimentary.

question:
A layer of solid brittle rock comprises the outer 100 kilometers of Earth. This layer, which contains both the crust and the upper mantle, is called the

answer:
lithosphere.