Question

What is the reducing agent in the reaction `2Na(s) + Cu(NO_3)_2(aq) -> Cu(s) +2NaNO_3(aq)`?

Answer 1

`"The reducing agent"` is the species oxidized........`"the electron source."`

Explanation:

And sodium is clearly the species oxidized here,

i.e. `NararrNa^+ +e^-`

I don't think this could be accomplished in aqueous solution. The sodium would reduce the water first to hydrogen gas.