The reaction of zinc with excess of aqueous alkali, evolves hydrogen gas and gives:
\( \mathrm{Zn(OH)_2} \)
\( \mathrm{ZnO} \)
\( [\mathrm{Zn(OH)_4}]^{2-} \)
\( [\mathrm{ZnO_2}]^{2-} \)