Raheema Javed
Last Activity: 10 Years ago
Boron only has 3 valence electrons (ns2 np1). So, with three flourine's attached, you'll form a covalent compound by sharing electrons. The compound now has 6 electrons, and it needs to have 8 (octet rule, though there are exceptions for some atoms). Anyhow, it can accept two more electrons to fill its octet.
Lewis Acid = Donate H, Accept e-
Lewis Base = Accept H, Donate e-
So, BF3 is a Lewis Acid. I think when a Lewis Base donates two electrons to the compound, it is called a "coordinate covalent bond." If the base is removed from the acid, it will take its two electrons with it.