why C-O bond in phenols is larger than that of alcohols. 

Asked by pfffxy571 | 8th Jun, 2018, 10:27: AM

Expert Answer:

The question should be: why C-O bond in alcohols is larger than that of phenols.
Phenol has a benzene ring with a -OH group attached to it, the lone pair of this oxygen of _OH group is in conjugation with the phenyl ring, hence the C-O bond will attain the partial double bond character, and the bond length of the double bond is shorter than the single bond.
Whereas in aliphatic alcohols there no such conjugation is there, hence the bond length of C-O of Alcohol is larger than that of the phenols.

Answered by Ramandeep | 8th Jun, 2018, 12:56: PM