what does this mean

[gotzmlk]

Using the ammonia molecule as an example, distinguish between shared pairs and unshared pairs of electrons.




and

Ch2Cl2

drawing lewis dot. which one would be central.

[repugno]

Bond pairs (shared pairs) of electrons are the electrons being shared between the atoms (i.e those involved in bonding). The lone pairs (unshared pairs) aren't involved in bonds but in some cases they can form dative covalent bonds where they are shared.