Answer:
Zn(OH)₂
Explanation:
Zn is above Fe in the activity series, so it is more readily oxidized:
Zn(s) ⟶ Zn²⁺(aq) + 2e⁻
The zinc ions go into solution.
The electrons travel from the Zn to the surface of the iron nail, where they reduce the water to hydrogen and hydroxide ions.
2H₂O(ℓ) + 2e⁻ ⟶ H₂(g) + 2OH⁻(aq)
Neither the zinc ions nor the hydroxide ions can move far through the gel.
Their concentration builds up around the hail. The ions find each other and form a precipitate.
Zn²⁺(aq) + 2OH⁻(aq) ⟶ Zn(OH)₂(s)
