WAEC Chemistry 2021 Paper

Concept:Alkanols are classified by the number of hydroxyl groups and by the type of carbon atom to which the hydroxyl group is attached.Explanation:The given structure is $\mathrm{HO{-}CH_2{-}CH_2{-}OH}$.This molecule contains two hydroxyl groups, so it is dihydric.Each carbon atom that carries an $\mathrm{-OH}$ group is bonded to only one alkyl carbon atom.That makes each hydroxyl-bearing carbon a primary carbon.Thus, the compound is a primary alcohol.It is not secondary or tertiary because no carbon bearing $\mathrm{-OH}$ is bonded to two or three carbon atoms.It is also not monohydric because there are two $\mathrm{-OH}$ groups present.Answer:The alkanol represented by the structure is A. primary and dihydric.