Each aluminium ion should have a charge of +2, because the sum of oxidation numbers must be zero.
The uncharged aluminium atom must lose two electrons to become an ion with +2 charge.
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The nucleus of an atom is made up of Protons and Neutrons.
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Answer: Atomic Nucleus!
Explanation: All atoms have a dense central core called the atomic nucleus. Forming the nucleus are two kinds of particles: protons, which have a positive electrical charge, and neutrons, which have no charge.
(Yes, it was from google.)