What amount of bromine will be required to convert 2 g of phenol into 2,4,6-tribromophenol? (Given molar mass in g mol-1 of C, H, O, Br are 12, 1, 16, 80 respectively )
(2) 10.22 g
Concept: –OH is o/p-directing, so all three o/p H are replaced ⇒ 1 mol phenol needs 3 mol Br2.
[figure]
94 g phenol ⇔ 3 × 160 = 480 g Br2
⇒ for 2 g: 480 294 = 10.22 g
Answer: (2)
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