Final answer:
Negative ions, or anions, are formed when atoms gain electrons.
Step-by-step explanation:
The subject of this question is Chemistry.
Negative ions, also known as anions, are formed when atoms gain electrons, not when they lose electrons. When an atom gains one or more electrons, it becomes negatively charged and forms a negative ion. For example, when a chlorine atom gains one electron, it becomes a chloride ion with a -1 charge.
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