Hello there!
Greetings!
Oxidation is simply addition of oxygen or removal of hydrogen or removal of electrons from a substance. For example, when Mg loses its 2 electrons, it gets oxidised into Mg2+. I didn't get second part of your question as oxidation is a process and not a species to react with something.
Thankyou
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile