Classify the isomers of alcohols in question 3. (i) as primary, secondary and tertiary alcohols.

(A) Primary alcohol

Explanation

(i) Pentan-1-ol

(ii) 2-Methylbutan-1-ol

(iii) 3-Methylbutan-1-ol

(iv) 2,2-Dimethylpropan-1-ol

The -OH group is attached to the carbon that is attached to another single carbon.

(B) Secondary alcohol

(i) Pentan-2-ol

(ii) 3-Methylbutan-2-ol

(iii) Pentan-3-ol

The -OH group is attached to the carbon that is attached to another two carbons.

(C) Secondary alcohol

(i) 2-Methylbutan-2-ol

The -OH group is attached to the carbon group that is further attached to another three carbon atoms.