Give reasons in two or three sentences only for the following
"The species`[CuCI_(4)]^(2-)` exitsts, while`[CuI_(4)]^(2-)` does not" .

Explanation

To explain why the species \([CuCl_4]^{2-}\) exists while \([CuI_4]^{2-}\) does not, we can consider the reducing properties of the ligands involved. The iodide ion (I\(^-\)) is a stronger reducing agent than the chloride ion (Cl\(^-\)). When copper(II) ions (\(Cu^{2+}\)) are coordinated with iodide ions, the iodide can reduce \(Cu^{2+}\) to \(Cu^+\), leading to the formation of copper(I) iodide (CuI), which means that the complex \([CuI_4]^{2-}\) cannot be stable. In contrast, chloride ions do not reduce \(Cu^{2+}\) to \(Cu^+\) effectively, allowing the complex \([CuCl_4]^{2-}\) to exist stably.

### Step-by-Step Solution:
1. **Identify the Ions**: Recognize that both complexes involve copper in the +2 oxidation state, \(Cu^{2+}\).
2. **Analyze the Ligands**: Compare the reducing abilities of the ligands: iodide (I\(^-\)) is a stronger reducing agent than chloride (Cl\(^-\)).
3. **Consider the Stability of Complexes**: Understand that the stronger reducing ability of iodide leads to the reduction of \(Cu^{2+}\) to \(Cu^+\), making \([CuI_4]^{2-}\) unstable and unable to exist, while \([CuCl_4]^{2-}\) remains stable because chloride does not reduce \(Cu^{2+}\).