Question

Oxidation means __________ of $O_2$ and reduction means _________ of hydrogen.

Answer 1

Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion. Oxidation is a gain of oxygen. Similarly, oxidation is a loss of hydrogen.

Reduction is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion. The reduction is a loss of oxygen. Similarly, a reduction is a gain of hydrogen.