Which of the following statements is incorrect?

Options

A. Mercurous ion exists as `Hg^(+)`
B. Mercurous ion is diamagnetic and exists as dimer `Hg_(2)^(2+)`
C. Mercurous ion is colourless
D. There is a metallic bond between two `Hg^(+)` ions

Answer

To solve the question, we need to analyze the given statements about the mercurous ion (Hg₂²⁺) and determine which one is incorrect. Here’s a step-by-step breakdown of the solution:

### Step 1: Analyze the Statements
We have four statements regarding the mercurous ion. We need to evaluate each one to see if it is true or false.

1. **Statement 1**: Mercurous ion exists as Hg⁺.
2. **Statement 2**: Mercurous ion is diamagnetic and exists as Hg₂²⁺.
3. **Statement 3**: Mercurous ion is colorless.
4. **Statement 4**: There is a metallic bond between two Hg ions.

### Step 2: Evaluate Each Statement

#### Statement 1: Mercurous ion exists as Hg⁺
- The mercurous ion is actually represented as Hg₂²⁺, which is a dimer of two Hg⁺ ions. Therefore, this statement is incorrect.

#### Statement 2: Mercurous ion is diamagnetic and exists as Hg₂²⁺
- The Hg₂²⁺ ion is indeed a dimer and is known to be diamagnetic because it has paired electrons. This statement is correct.

#### Statement 3: Mercurous ion is colorless
- Mercurous ions (Hg₂²⁺) are generally colorless in solution. This statement is also correct.

#### Statement 4: There is a metallic bond between two Hg ions
- In the dimer Hg₂²⁺, there is a metallic bond between the two mercury atoms. This statement is correct.

### Step 3: Conclusion
Based on the evaluations:
- The incorrect statement is **Statement 1**: "Mercurous ion exists as Hg⁺".

### Final Answer
The incorrect statement is: **Mercurous ion exists as Hg⁺**.

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