When a molecule of nad plus gains a hydrogen atom to become nadh does the molecule become phosphorylated or oxidized or reduced or redoxed?

Answer 1

When NAD+ becomes NADH gaining that hydrogen it also gains an electron(s), which is its actual job. So, it becomes reduced.

Answer 2

When a molecule of NAD+ gains a hydrogen atom to become NADH, the molecule is reduced. Reduction is the gain of electrons by a molecule, which is what occurs in this process. This is part of a redox (reduction-oxidation) reaction where one molecule is reduced (NAD+) and the other molecule is oxidized (loses electrons).