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- Atomic nucleus: its formed by ( protons, electrons ) and neutrons, and it's in the ( middle of the atom, outside of the atom ), occupying a very ( small, big ) space relative to the rest of the atom.
- ( Rest of the atom, Out part, Helmet ): also called the shell. ( Electrons, Protons, Neutrons ) occupy the empty space around each atomic nucleus. Scientists thought electrons ( orbited, surrounded, jumped ) the nucleus.