If fluorine was in ionic compounds with ions of each of the following atoms, how many fluorines would be needed?

A. Sodium

4

B. Magnesium

1

C. Aluminum

3

D. Silicon

2

A. Sodium = 1

B. Magnesium = 2

C. Aluminum = 3

D. Silicon = 4

Fluorine is a halogen group that needs 1 more electron to become stable. When it forms a compound with other, the number of fluor atoms depends on the valence electron of the couple. Sodium has 1 valence electron while magnesium has 2, aluminum has 3 and silicon has 4