Naming The Formula PbS


Naming The Formula PbS

Name the formula PbS.  In order to name the compound, the ions in it must be identified. By referring to a ion table or typical common cation and anion list, three likely ions can be found: lead(II), lead(IV) and sulfide. They are  Pb+2, Pb+4 and S-2. This allows for two separate lead and sulfur compounds. Namely lead(II) sulfide and lead(IV) sulfide The process can be visualized as follows:

   lead(II) sulfide                 lead(IV) sulfide

   (Cation)x(Anion)y          (Cation)x(Anion)y

   (Pb+2)x(S-2)y                 (Pb+4)x(S-2)y

Cross over the ion charges to produce the subscripts:

   (Pb+2)2(S-2)2                   (Pb+4)2(S-2)4

Reduce the subscripts to the lowest ratio:

   (Pb+2)1(S-2)1                    (Pb+4)1(S-2)2

Remove the charges since the are no longer needed:

   (Pb)1(S)1                             (Pb)1(S)2

Do not show subscripts that are “1":

   (Pb)(S)                                   (Pb)(S)2

Sn and S are not polyatomic not parenthesis are needed

   PbS                                            PbS2

The name for PbS is lead(II) sulfide.


© Pat Thayer 2014-2016