Phenol is treated with dilute HNO₃ to form a nitrated product. After distillation, the filtrate is collected. The percentage change in oxygen content from phenol to the product in the filtrate is x%. Find the value of 2x.

When phenol reacts with dilute nitric acid, a mixture of ortho-nitrophenol and para-nitrophenol is formed. During steam distillation, ortho-nitrophenol distils over because of intramolecular hydrogen bonding, while para-nitrophenol remains in the filtrate due to intermolecular hydrogen bonding.

Therefore, the product present in the filtrate is:

p-Nitrophenol (C₆H₅NO₃)

For phenol:

C₆H₆O

Molar mass:

72 + 6 + 16 = 94

Percentage oxygen:

(16/94) × 100 = 17.02%

For p-nitrophenol:

C₆H₅NO₃

Molar mass:

72 + 5 + 14 + 48 = 139

Percentage oxygen:

(48/139) × 100 = 34.53%

Percentage increase:

34.53 − 17.02 = 17.51%

Thus:

x ≈ 17.5

Therefore:

2x = 35

This problem combines concepts of aromatic substitution, nitration of phenol, steam distillation, and percentage composition calculations.

2x = 35