Final answer:
The correct equation for the dissociation of calcium chloride (CaCl₂) in water is CaCl₂ (s) → Ca²⁺ (aq) + 2Cl⁻ (aq), producing one calcium ion and two chloride ions.
Step-by-step explanation:
When calcium chloride (CaCl₂) dissociates in water, it separates into ions. The correct equation that represents its dissociation is:
CaCl₂ (s) → Ca²⁺ (aq) + 2Cl⁻ (aq)
This equation shows that one formula unit of calcium chloride produces one calcium ion with a 2+ charge, and two chloride ions each with a 1- charge. This maintains electrical neutrality as the positive and negative charges balance out. This process also increases the amount of energy released compared to forming just CaCl, making CaCl₂ more stable and therefore the preferred compound.