Every atom has a PROTON and an ELECTRON.
Not every atom has a NEUTRON. Hydrogen is the ONLY ATOM that has no neutron. All the others do.
These are the three particles of atoms: PROTONS, NEUTRONS, ELECTRONS.
Protons and neutrons are in the NUCLEUS.
Electrons orbit around the nucleus in SHELLS.
We use the BOHR model to understand the STRUCTURE of atoms.
![Picture](/uploads/1/0/0/1/10014792/7299924.gif)
This is not what they actually look like. They look more like clouds.
![Picture](/uploads/1/0/0/1/10014792/6800480.jpg)
All the elements in the known universe can be reduced to a single atom. An atom is the smallest form of matter that connote be divided without changing into something else. All the elements are organized onto the Periodic Table of Elements. We give it this name because all the elements are organized into rows called PERIODS. The person who first did this was a Russian man named Dimitri Mendeleev.
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Periodic Table of Elements.