Concept:Thermodynamic definitions are strictly linked to the physical states of the reactants and products shown in the chemical equation.
Formula:$$ \text{Cation}_{(g)} + \text{Anion}_{(g)} \rightarrow \text{Ionic Crystal}_{(s)} $$
Solution:- The equation shows isolated gaseous ions (\( Mg^{2+} \) and \( O^{2-} \)) coming together to form a solid crystal lattice (\( MgO_{(s)} \)).
- The massive amount of energy released during this highly specific phase and structural transition is universally defined as the Lattice energy (or Lattice enthalpy of formation).
Why other options are incorrect:Atomization forms gaseous atoms from a solid, not a solid from gaseous ions. Neutralization involves \( H^+ \) and \( OH^- \) forming liquid water. Solution involves dissolving a solid into aqueous ions.
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