Sleep Number King Size 2-3 inch Mattress Bed Foam Topper Pad 7000, i8, i9.
Quick Answer. The three parts of an atom are the protons, neutrons and electrons. Atoms make up the basic building blocks of matter and define the structure of elements. These parts were not officially identified until 1932.
Atoms: A single unit of an element is called an atom. The atom is the most basic unit of matter, which makes up everything in the world around us. Each atom retains all of the chemical and physical properties of its parent element.