which electrons are involved in the bonding
So all in all, there are 6 electrons that are involve in the bonding (3 bonding pairs) and 2 electrons that are non-bonding (1 non-bonding pair) since the two of its valence electrons did not pair up to form a bond. Carbon on the other hand has 4 valence electrons coming from Group IVA and thus will need four electrons more to have an 8. Each of these 4 valence electrons will pair up with an incoming. atom to form 4 bonds and consequently will have four bonding pairs and none non-bonding pair.