Ncert Exercises & Solutions

Which of the following compounds (i) and (ii) will not react with a
mixture of NaBr and $H_{2} S O_{4}$ . Explain why?

(i) $C H_{} C H_{2} C H_{2} O H$

Partial double bond character uf a bond increses the strength of the bond and hence,

decreases the stability. Phenol will not react with a mixture of NaBr and $H_{2} S O_{4}$ because it is

resonance stabilised. Due to resonance, partial double bond character arises in C—O

bond of phenol and it becomes more stable than alcohol $(C H_{3} C H_{2} C H_{2} O H) .$

Reaction $2 N a B r + 3 H_{2} S O_{4} \to 2 N a H S O_{4} + S O_{2} B r_{2} + 2 H_{2} O$