Is Cu(OH)2 insoluble or soluble
The Correct Answer and Explanation is:
Copper(II) hydroxide, Cu(OH)2, is considered insoluble in water. This means that when Cu(OH)2 is added to water, only a very small amount will dissolve, while the majority will remain as a solid.
The solubility of ionic compounds in water depends on the ability of water molecules to separate the ions that make up the compound. In the case of Cu(OH)2, it dissociates into copper ions (Cu²⁺) and hydroxide ions (OH⁻). However, due to the strong electrostatic attraction between these ions, Cu(OH)2 does not dissolve easily in water.
The solubility product (Ksp) of Cu(OH)2 is quite low, indicating that only a very small amount will dissociate into its constituent ions. The Ksp for Cu(OH)2 is approximately 2.2 × 10⁻ at 25°C, which means that in a saturated solution, the concentration of Cu²⁺ and OH⁻ ions is extremely low.
Furthermore, Cu(OH)2 is a classic example of a compound that shows a relatively low solubility in water compared to other metal hydroxides. This low solubility can be attributed to the strong lattice energy of Cu(OH)2, which makes it difficult for water molecules to break apart the solid and separate the ions.
In addition to this, Cu(OH)2 is also amphoteric, meaning it can react with both acids and bases. In the presence of a strong acid, Cu(OH)2 will dissolve by reacting to form copper salts, such as CuCl2. Similarly, in a strongly basic environment, Cu(OH)2 can dissolve by reacting with excess hydroxide ions to form copper(II) complexes.
In summary, while Cu(OH)2 is insoluble in water under normal conditions, its solubility can be increased by changing the pH of the solution.
