Neutralization reaction for CuCl₂ preparation

Steps:

• Identify CuCl₂ as a soluble ionic salt requiring acid-base or displacement methods.
• Evaluate options for feasibility: must produce Cu²⁺ and Cl⁻ ions safely in lab.
• Check copper's reactivity: inert to dilute acids without oxidation.
• Select method yielding pure product without side reactions or hazards.

Why D is correct:

• CuO + 2HCl → CuCl₂ + H₂O; metal oxide neutralizes acid to form salt directly.

Why the others are wrong:

• A: No reaction; spectator ions form no precipitate or drive equilibrium.
• B: Exothermic, produces toxic Cl₂ gas; not controlled for lab.
• C: No reaction; Cu below H in reactivity series, no H₂ evolution.

Final answer: D