Chemical properties of monohydric alcohols

Characteristic reaction of alcohol are the reaction of the - OH group. The reactions of the hydroxyl group includes either cleavage of C - O bond or the cleavage of O - H bond.

C - O bond is weaker or weak in the case of tertiary alcohols because of +I effect of alkyl groups whereas - OH bond is weak in primary alcohols as electron density increase among O - H bond and hydrogen tends to separates as a proton.

So primary alcohols provide the most of reaction by cleavage of O - H bond whereas tertiary alcohols are most reactive due to cleavage of C - O bond. Therefore - O - H cleavage reactivity order:

Primary > Secondary > Tertiary 

and C - O - cleavage reactivity order :

Tertiary > Secondary > Primary alcohol