The formula COH₂ is not a stable compound. It's likely a typo. However, let's assume it's meant to be a combination of common elements:

If you meant CH₂O (formaldehyde):

* C (Carbon): The oxidation state of carbon in formaldehyde is 0. This is because it's bonded to two hydrogens (+1 each) and one oxygen (-2). The total oxidation state of the molecule is 0, so the carbon must be 0 to balance it out.

* H (Hydrogen): The oxidation state of hydrogen in most compounds is +1.

* O (Oxygen): The oxidation state of oxygen in most compounds is -2.

If you meant something else, please clarify the formula!