When copper(II) sulfate, CuSO4, dissolves in water, both of the resulting ions can become hydrated. (a) Write a balanced chemical equation that shows copper(II) sulfate dissolving in water and the hydration of Cu2+ with 4 water molecules and SO42- with 14 water molecules. (Complex ions take the general form: Cu(NH3)4^2+). Omit states-of-matter from your answer.
The Correct Answer and Explanation is:
The dissolution of copper(II) sulfate in water can be represented by the following equation:
CuSO4 → Cu^2+ + SO4^2-
When CuSO4 dissolves in water, it dissociates into copper(II) ions (Cu^2+) and sulfate ions (SO4^2-). Both ions are then surrounded by water molecules, a process called hydration, which stabilizes the ions in the aqueous solution. The hydration of Cu^2+ and SO4^2- can be represented as follows:
Cu^2+ + 4H2O → [Cu(H2O)4]^2+
SO4^2- + 14H2O → [SO4(H2O)14]^2-
Thus, the complete process of dissolution and hydration can be expressed by combining the dissociation and hydration equations:
CuSO4 + 18H2O → [Cu(H2O)4]^2+ + [SO4(H2O)14]^2-
Explanation:
- Dissociation of CuSO4: Copper(II) sulfate dissociates into two ions in water. CuSO4 is a salt, and when it is placed in water, it separates into Cu^2+ and SO4^2- ions. This is a typical process for soluble ionic compounds.
- Hydration of Cu^2+: After the Cu^2+ ion is released into the solution, it becomes surrounded by water molecules. In this case, 4 water molecules surround the Cu^2+ ion, forming the complex ion [Cu(H2O)4]^2+. This is an example of a hydrated metal ion, where the water molecules coordinate with the metal ion.
- Hydration of SO4^2-: Similarly, the sulfate ion (SO4^2-) is also surrounded by water molecules, forming a hydrated complex [SO4(H2O)14]^2-. In this case, 14 water molecules surround the sulfate ion.
- Overall Process: The final equation shows the dissociation of CuSO4 into its ions and the hydration of these ions, forming a stable aqueous solution.
