Answer: Ions result from atoms or molecules that have gained or lost one or more valence electrons, giving them a positive or negative charge. Those with a negative charge are called anions and those with a positive charge are called cations. Cations (positively-charged ions) and anions (negatively-charged ions) are formed when a metal loses electrons, and a nonmetal gains those electrons. ... And all of them form an anion with a single negative charge. The VIA elements gain two electrons to form anions with a 2- charge.
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