[Heisenberzerk]

Before I say anything else : making iron oxide this way releases a toxic gas that can be deadly.

Hello, I'm making some iron oxide with steel wool from :
- bleach (3,7% by weight) and
- white vinegar (8%)
After some time I juste filter out what's left with cofee filters.

I was wondering if there is an ideal ratio for this reaction ? I know acetic acid is used to lower the pH of the solution but not much more.
Are there any impurities formed with this ? if yes how can I minimize them and how can I get them out of the final product?

Thanks