Final answer:
An O negative ion is an atom with fewer neutrons than protons and more electrons than protons.
Step-by-step explanation:
An atom that has fewer neutrons than protons and more electrons than protons is an O negative ion. In this case, the atom has gained extra electrons, giving it a negative charge. The O negative ion is formed by the element oxygen, which has eight protons and typically eight neutrons in its nucleus.
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