Question

Does Oxidation involve the increase of Hydrogen (H) atoms also or does it only refer to increase in Oxygen atoms (O)?

Answer 1

oxidation means gaining of electron

here ,not oxygen , hydrogen will oxide to be configuration of helium

Answer 2

Oxidation involves increase in the oxidation number which is primarily due to the loss of electrons  , in other it's said oxidation is the addition of an electronegative element like oxygen or removal of an electropositive element like hydrogen.