Question

How do you draw an atomic level diagram for 2S+3O2=2SO3 ?

Answer 1

I think you are asking how to show the way the atoms combine in the reaction.

Explanation:

The easiest way is first to break up the `"O"_2` molecules into atoms.

`"O"_2 → 2"O"`

Then we can re-write the equation for the reaction as

`"2S + 6O → 2SO"_3`

or

`"1S + 3O → 1SO"_3`

The `"S"` atom in `"SO"_3` is in the middle with three `"O"` atoms attached to it.

If we want to show how the atoms combine, the diagram might look like this:

Structure A isn't a good structure, because it doesn't give the `"S"` atom eight valence electrons.

So we use a pair of electrons from an `"O"` atom to form an `"S=O"` double bond (Structure B).

Structure B still isn't the best structure for `"SO"_3`, but it gives every atom an octet in its valence shell.

If this isn't what you wanted, please let me know.