In the given reaction
`C_(6)H_(5)-OHoverset(H_2SO_4)(rarr) underset("as major product")(X) underset(Delta)overset((i)NaOH)(rarr)(Y)`
`'Y'` is

Options

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B.
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D.

Answer

To solve the problem step by step, we will analyze the given reaction and identify the major product (Y) formed after the reactions.

### Step 1: Identify the starting compound
The starting compound is phenol, represented as \( C_6H_5OH \).

### Step 2: Reaction with \( H_2SO_4 \)
When phenol reacts with concentrated sulfuric acid (\( H_2SO_4 \)), it undergoes electrophilic substitution. The \( H_2SO_4 \) can introduce a sulfonyl group (\( SO_3H \)) to the aromatic ring.

- The hydroxyl group (\( OH \)) in phenol is an ortho/para directing group, but because \( SO_3H \) is bulky, it will preferentially attach to the para position due to steric hindrance.
- The product formed after this reaction (let's call it \( X \)) will be para-hydroxybenzene sulfonic acid, which can be represented as \( C_6H_4(OH)(SO_3H) \).

### Step 3: Reaction with \( NaOH \)
Next, the product \( X \) (para-hydroxybenzene sulfonic acid) is treated with sodium hydroxide (\( NaOH \)).

- In this step, \( OH^- \) acts as a strong nucleophile and will attack the sulfonic acid group (\( SO_3H \)), leading to the elimination of \( HSO_3^- \) (the leaving group).
- The result of this reaction will be the formation of a compound with two hydroxyl groups, specifically para-dihydroxybenzene (also known as hydroquinone), represented as \( C_6H_4(OH)(OH) \).

### Step 4: Conclusion
Thus, the final product \( Y \) is para-dihydroxybenzene.

### Final Answer
The product \( Y \) is para-dihydroxybenzene.

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