Question

Why magnesium metal cannot be obtained by carbon reduction?​

Answer 1

Answer:

Why can't magnesium be extracted from its ore by reduction with carbon?

Because Mg is higher up on the metal reactivity series than carbon. That is, magnesium is more likely to lose electrons than carbon is. A more likely reaction would be the oxidation of magnesium metal when combined with carbon :

Mg(s) + electrolyte(aqueous salt/acid) + C(s) > Mg2+(aq) + reduced electrolyte cation + C(s)

Here, magnesium metal serves as an anode/source of electrons and carbon functions as a cathode where reduction of an electrolyte/aqueous cation takes place. Due to their different electronegativities (affinity/attraction for an electron), negative charge/ electrons are more likely to move from magnesium to carbon, than the other way around.

Answer 2

As magnesium is an element with a greater reactivity than carbon. Magnesium, on the other hand, is more prone to lose electrons than carbon. The oxidation of magnesium metal, when coupled with carbon, is a more likely reaction:

Magnesium metal acts as an anode (a source of electrons) while carbon acts as a cathode (a site where an electrolyte/aqueous cation is reduced). Negative charge/ electrons are more likely to flow from magnesium to carbon than the other way around due to their varied electronegativities (affinity/attraction for an electron).

Mg(s) + electrolyte(aqueous salt/acid) + C(s) > Mg2+(aq) + reduced electrolyte cation + C(s)