Question

How can I draw the Lewis structure for ClO2-?

Answer 1

Here's how I would do it.

Explanation:

You can find the procedure here.

For `"ClO"_2^"-", "Cl"` is the less electronegative atom. So, `"Cl"` is the central atom

The skeleton structure is `"O-Cl-O".`

The trial structure is

You have 20 valence electrons in your trial structure.

The valence electrons you have available are: `"1 Cl + 2 O + 1 e" = 1×7 + 2×6 + 1 = 20`.

Hence, the trial structure has the correct number of electrons.

The formal charge on each atom is:

`"Cl" = 7 - 4 - ½(4) = +1; "O" = 6 – 6 - ½(2) = "-1"`

Every atom has a formal charge.

We can reduce the number of formal charges by moving a lone pair of electrons from `"O"` to form a `"Cl=O"` double bond.

This gives us two new structures in which one `"O"` atom has `"FC = -1"` and the other atoms have `"FC = 0"`:

The actual structure is nine of these. Rather, it is a resonance hybrid of them both