# Extraction of metals using electrolysis

I came across a question that goes as:

The electrolytic method of reduction is employed for the preparation of metals that are:

1. Less electropositive
2. Moderately electropositive
3. Highly electropositive

I was thinking that highly electropositive metals like Na+, Li+ and others which have highly negative reduction potentials should be difficult to reduce as hydrogen would be preferentially reduced. For example, in electrolysis of NaCl, Na+ is left in the solution as NaOH while it is hydrogen that is reduced.

However the answer is highly electropositive metals. I searched for the reason elsewhere but did not find it.

With plentiful electricity, the cost of producing aluminum has dropped to ~US\$2/kg, and electrolytically produced sodium is ~US\$4,000/tonne.