Answer:
[tex]CaCl_2[/tex]
Explanation:
Calcium is the element of the group 2 and period 4 which means that the valence electronic configuration is [tex][Ar]4s^2[/tex].
Chlorine is the element of the group 17 and period 3 which means that the valence electronic configuration is [tex][Ne]3s^23p^5[/tex].
Thus, calcium losses 2 electrons to 2 atoms of chlorine and these 2 atoms of chlorine accepts each electron to form ionic bond. This is done in order that the octet of the atoms are complete and they become stable.
Ca Cl
2 1
Cross multiplying the valency, We get, [tex]CaCl_2[/tex]
Thus, the formula of calcium chloride is [tex]CaCl_2[/tex].