Commonly Tested Lewis Structures

We draw Lewis Structures to predict:

-the shape of a molecule.

-the reactivity of a molecule and how it might interact with other molecules.

-the physical properties of a molecule such as boiling point, surface tension, etc.

Drawing the Lewis Structure for PO43-

Video: Drawing the Lewis Structure for PO43-

For the PO4 3- Lewis structure use the periodic table to find the total number of valence electrons for the PO4 3- molecule. Once we know how many valence electrons there are in PO4 3- we can distribute them around the central atom with the goal of filling the outer shells of each atom.

In the Lewis structure of PO43- there are a total of 32 valence electrons.

For the Lewis structure for PO4 3- you should take formal charges into account to find the best Lewis structure for the molecule. Remember, PO4 3- has a negative three charge on the molecule. For the Lewis structure you'll need to have a total charge for the molecule of 3-.


It is helpful if you:

  • Try to draw the PO43- Lewis structure before watching the video.
  • Watch the video and see if you missed any steps or information.
  • Try structures similar to PO43- for more practice.

List of Lewis Structures

Acetone BF3 BH4- BrF5 BrO3- C2H2 C2H4 ClO-
CH4 ClO2- ClO2 ClO4- CO CS2 H2O H3O+
HCl HNO3 I3- ICl4- IF5 N2 N3- NH2OH
NH3 NO2- NO2 NO3- O2 OF2 PCl5 PH3
PO33- PO43- SCl2 SF4 SF6 SO3 SO42- XeF2
XeF4