`CH_(3)-CequivCHunderset(1%HgSO_(4))overset(40%H_(2)SO_(4))toAoverset("isomerisation")toCH_(3)-underset(O)underset(||)C-CH_(3)`
Structure of 'A' and type of isomerism in the above reaction are respectively.

Options

A. Prop-1-en-2-ol, metamerism
B. Prop-1-en-l -ol, tautomerism
C. Prop-2-en-2-ol, geometrical isomerism
D. Prop-1-en-2-ol, tautomerism

Explanation

To solve the problem, we need to analyze the reaction step by step.

### Step 1: Identify the Reactants
The reactant is an alkyne, specifically 1-butyne (CH₃-C≡CH). This alkyne will react with 1% HgSO₄ and 40% H₂SO₄.

### Step 2: Understand the Reaction Conditions
In the presence of HgSO₄ and H₂SO₄, the alkyne undergoes hydration. The Hg²⁺ acts as a catalyst, and H⁺ from H₂SO₄ provides the acidic medium necessary for the reaction.

### Step 3: Apply Markovnikov's Rule
According to Markovnikov's rule, when water adds to an alkyne, the hydrogen (H) will add to the carbon with more hydrogen atoms, and the hydroxyl group (OH) will add to the carbon with fewer hydrogen atoms.

For 1-butyne (CH₃-C≡CH):
- The H⁺ will add to the terminal carbon (CH₃), and the OH will add to the internal carbon (C≡C).

### Step 4: Determine the Product 'A'
The product formed after the addition of water to the alkyne will be:
- CH₃-CH(OH)-CH₃ (which is 2-butanol).

### Step 5: Identify the Isomerization Process
The product 'A' (2-butanol) can undergo isomerization. In this case, the isomerization is known as tautomerism, where the hydrogen atom shifts from the hydroxyl group to the adjacent carbon, resulting in the formation of a carbonyl compound.

### Step 6: Final Product After Isomerization
After tautomerization, the product will be:
- CH₃-C(=O)-CH₃ (which is acetone).

### Conclusion
The structure of 'A' is 2-butanol (CH₃-CH(OH)-CH₃), and the type of isomerism involved in the reaction is tautomerism.

### Final Answer
- Structure of 'A': 2-butanol (CH₃-CH(OH)-CH₃)
- Type of isomerism: Tautomerism

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