Consider the following statements about solvate isomerism.
I. It is also known as 'hydrate isomerism' where water is involved as a solvent.
II. It is also similar to ionisation isomerism.
III.Aqua complex`[Cr(H_2O)_6]Cl_3`(violet) is an example of solvate isomerism. Its solvate isomer is `[Cr(H_2O)_6Cl]Cl_2*H_2O.`
The correct set of statement (s) is /are

Options

A. I and II
B. II and III
C. I and III
D. All of these

Answer

To solve the question regarding the statements about solvate isomerism, we will analyze each statement one by one.

### Step 1: Analyze Statement I
Statement I claims that solvate isomerism is also known as "hydrate isomerism" where water is involved as a solvent.

**Solution**: This statement is **correct**. Solvate isomerism indeed refers to isomers that differ in the number of solvent molecules (like water) coordinated to the metal ion. When water is the solvent, it is specifically referred to as hydrate isomerism.

### Step 2: Analyze Statement II
Statement II states that solvate isomerism is similar to ionization isomerism.

**Solution**: This statement is also **correct**. Solvate isomerism involves the exchange of solvent molecules and can be compared to ionization isomerism, where the position of counter ions and solvent molecules can lead to different isomers. Both types of isomerism involve the rearrangement of ligands around the central metal ion.

### Step 3: Analyze Statement III
Statement III provides an example of solvate isomerism with the aqua complex `[Cr(H2O)6]Cl3` (violet) and its solvate isomer `[Cr(H2O)6Cl]Cl2·H2O`.

**Solution**: This statement is **correct** as well. The example given illustrates solvate isomerism where the chloride ion is coordinated to the chromium ion, and a water molecule is present as a solvent, demonstrating the change in the arrangement of ligands.

### Conclusion
After analyzing all three statements, we find that all of them are correct. Therefore, the correct answer to the question is that all statements are true.

### Final Answer
The correct set of statements is: **All of the above (Option 4)**.

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