Name the ionisation isomer of `[Cr(H_2O)_5Cl]SO_4`.

Explanation

To determine the ionization isomer of the complex ion \([Cr(H_2O)_5Cl]SO_4\), we need to understand what ionization isomers are and how they differ from each other.

### Step-by-Step Solution:

1. **Identify the Coordination Complex**: The given complex is \([Cr(H_2O)_5Cl]SO_4\). Here, chromium (Cr) is the central metal ion, and it is coordinated to five water molecules (H2O) and one chloride ion (Cl).

2. **Understand Ionization Isomers**: Ionization isomers are compounds that have the same formula but differ in the ions that are released when they dissolve in water. This means that the composition of the ions in solution can vary based on how the ligands are arranged around the central metal ion.

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