The product of a Lewis acid-base reaction is a(n) , a single species that contains a new covalent bond. The Lewis acid-base definition focuses on the donation or acceptance of an electron pair to form a new covalent bond in an adduct, the product of an acid-base reaction. Lewis bases the electron pair, and Lewis acids it.

Adduct, donate, accept

Explanation:

Lewis acids are those having suitable vacant orbital for electron acceptance and forming a covalent bond with an electron rich species. Example: (B has vacant 2p orbital for electron acceptance)

Lewis bases are those having energetically available unshared electrons that can be donated to an electron deficient species and form a covalent bond. Example: (N has energetically available lone pair)

So, product of Lewis acid-base reaction is an adduct () where a new covalent bond is formed between B and N.

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.