Chemistry
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Atoms and molecules
Electrical neutrality of the atom
All atoms are electrically neutral and therefore have the same number of positive and negative charges.
Each electron has a negative electrical charge so there are as many electrons in an atom as positive electrical charges in its nucleus.
As a result:
- If the number of positive charges in a nucleus is known, then the number of elecrons around this nucleus is known too.
- If the number of electrons in an atom is known, then the number of positive charges in the nucleus is known too.
- If a compound has an electric charge ( positive or negative ) then this compound is not an atom (it is an ion).
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