Answer: Magnesium Mg
Explanation:
Oxidization is the process by which a substance either gains oxygen or losses electrons.
The chemical reaction of the above is denoted by,
Mg(s) + 2HCl(aq) -----> MgCl2(aq) + H2(g)
Mg went from a 0 to a +2 state which would mean that it lost electrons.
It was therefore oxidized.
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