Answer: Option (a) is the correct answer.
Explanation:
When an atom donates electrons to another atom then it results in the formation of a bond known as ionic bond.
For example, atomic number of calcium is 20 and its electronic distribution is 2, 8, 8, 2. Whereas atomic number of fluorine is 9 and its electronic distribution is 2, 7. So, in order to attain stability calcium loses two electrons and fluorine will gain one electron.
Therefore, calcium will combine with two fluorine atoms resulting in formation of a [tex]CaF_{2}[/tex] compound known as calcium fluoride.
