Read the passage carefully and answer the Questions.
Alcohols and phenols are obtained when a hydrogen atom in aliphatic and aromatic hydrocarbons respectively, is replaced by - OH group. These compounds find wide applications in industry as well as in our daily life. You may notice that ordinary spirit is used for polishing wooden furniture which is chiefly a compound containing hydroxyl group. An alcohol contains one or more hydroxyl (OH) group(s) directly attached to carbon atom(s), of an aliphatic system (\( CH_3OH \)) while a phenol contains -OH group(s) directly attached to carbon atom(s) of an aromatic system (\( C_6H_5OH \)). Alcohols are prepared by the hydration of alkenes, fermentation of glucose, and reduction of carbonyl compounds. Alcohols produce alkenes upon dehydration whereas alkenes on acid catalyzed hydration convert into alcohols.
Chemical formula of spirit used in polishing wooden furniture is
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → \(C_2H_5OH\)
Compounds with an –OH group have many everyday uses. The ordinary spirit used for polishing wooden furniture is mainly ethanol, the two-carbon alcohol, \( \ce{C2H5OH} \) (condensed formula \( \ce{CH3CH2OH} \)). It dissolves the resins of the polish and evaporates quickly, leaving the polish on the wood.
So the formula of the spirit is \( \ce{C2H5OH} \).
Note: In the original NTA paper, Option (3) was printed as \( \ce{CH3CH2OH} \), which is the same compound as Option (2) \( \ce{C2H5OH} \) (ethanol) written as a condensed formula. So that students are not confused and the question has a single answer, Option (3) has been changed to \( \ce{CH3CH2CH2OH} \) (propan-1-ol).