Choose the correct balanced chemical equation for the ionic dissociation of aluminum sulfate, Al2(SO4)3, in water: Al2(SO4)3 (aq) → 2 Al3+ (aq) + 3 SO4^2- (aq)
The Correct Answer and Explanation is:
The correct balanced chemical equation for the ionic dissociation of aluminum sulfate (Al2(SO4)3) in water is:Al2(SO4)3(aq)→2Al3+(aq)+3SO42−(aq)\text{Al}_2(\text{SO}_4)_3 (aq) \rightarrow 2 \text{Al}^{3+} (aq) + 3 \text{SO}_4^{2-} (aq)Al2(SO4)3(aq)→2Al3+(aq)+3SO42−(aq)
Explanation:
When aluminum sulfate (Al2(SO4)3) dissolves in water, it dissociates into its constituent ions. To break down the process:
- Aluminum Sulfate Structure: Aluminum sulfate is an ionic compound composed of aluminum ions (Al^3+) and sulfate ions (SO4^2-). The subscript “2” in Al2(SO4)3 means there are two aluminum ions (Al^3+) for every three sulfate ions (SO4^2-).
- Dissociation Process: When aluminum sulfate dissolves in water, the ionic bonds between the Al^3+ ions and SO4^2- ions are broken due to the interaction with water molecules. The water molecules surround the individual ions, stabilizing them in the solution.
- The formula unit Al2(SO4)3 consists of two aluminum ions (Al^3+) and three sulfate ions (SO4^2-).
- The dissociation results in the release of 2 Al^3+ ions and 3 SO4^2- ions per formula unit of Al2(SO4)3.
- Balanced Equation: The dissociation process is represented as: Al2(SO4)3(aq)→2Al3+(aq)+3SO42−(aq)\text{Al}_2(\text{SO}_4)_3 (aq) \rightarrow 2 \text{Al}^{3+} (aq) + 3 \text{SO}_4^{2-} (aq)Al2(SO4)3(aq)→2Al3+(aq)+3SO42−(aq) Here, the number of aluminum and sulfate ions on both sides of the equation is balanced. The number of aluminum ions (2 Al^3+) and sulfate ions (3 SO4^2-) on the right side matches the stoichiometric coefficients from the formula of aluminum sulfate on the left side.
Thus, the dissociation is complete and this balanced equation accurately represents the ionic dissociation of aluminum sulfate in water.
