Answer:
A) gain an electron and increase in size
Explanation:
Fluorine is a Group 17 element, making it a halogen. This means that it has 7 valence electrons in its outer shell. It only needs one more electron to fill its outer shell and gain stability. When fluorine becomes an ion, it gains an electron and becomes F⁻. Adding electrons creates a larger ion because the electrons occupy a larger volume due to mutual repulsions pushing them apart.
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