Answer:
Mg(s) + 2H⁺(aq) ⟶ Mg²⁺(aq) + H₂(g)
Explanation:
A net ionic equation shows all the ionic substances as ions and shows the correct state of each substance.
B. is wrong. HCl ionizes in aqueous solution into H⁺ and Cl⁻.
C. is wrong. Mg²⁺ is not a solid. It is an aqueous ion.
D. is wrong. The equation needs 2H⁺(aq) to be balanced.