Which statement`(s)` is/are correct ?
`i.` In oxymercuration and demercuration reaction, the electrophile is `AcOHg^(o+)`.
`ii.` In this reaction, `Hg^(+)` is reduced to `Hg^(0)`.
`iii.` In this reaction, `Hg^(2+)` is reduced to `Hg^(+)`
`iv.` In this reaction, `Hg^(2+)` is reduced to `Hg^(0)`.

Options

A. `(i)` and `(iv)`
B. `(i)` and `(ii)`
C. `(i)` and `(iii)`
D. `(iv)`

Answer

To determine which statements about the oxymercuration and demercuration reaction are correct, we will analyze each statement step by step.

### Step 1: Understand the Oxymercuration and Demercuration Reaction
In the oxymercuration and demercuration reaction, we typically start with an alkene and react it with mercuric acetate (Hg(OAc)₂). The reaction involves the formation of an electrophile, which is HgOAc⁺.

### Step 2: Analyze Statement i
**Statement i:** "In oxymercuration and demercuration reaction, the electrophile is AcOHg^(o+)."

- The electrophile in this reaction is indeed HgOAc⁺ (or AcOHg⁺). Therefore, this statement is **correct**.

### Step 3: Analyze Statement ii
**Statement ii:** "In this reaction, Hg^(+) is reduced to Hg^(0)."

- In the oxymercuration and demercuration process, the oxidation state of mercury changes from +2 (Hg²⁺) to 0 (Hg⁰) during the reduction step. Therefore, this statement is **incorrect**.

### Step 4: Analyze Statement iii
**Statement iii:** "In this reaction, Hg^(2+) is reduced to Hg^(+)."

- This statement is also incorrect because the mercury ion (Hg²⁺) is reduced to Hg⁰, not Hg⁺. Thus, this statement is **incorrect**.

### Step 5: Analyze Statement iv
**Statement iv:** "In this reaction, Hg^(2+) is reduced to Hg^(0)."

- This statement is correct. The mercury ion (Hg²⁺) is indeed reduced to Hg⁰ during the reaction. Therefore, this statement is **correct**.

### Conclusion
Based on the analysis:
- **Correct Statements:** i and iv
- **Incorrect Statements:** ii and iii

### Final Answer
The correct statements are **i and iv**.

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