Question

9 mark for review which of the following molecules contains only single bonds? a ch3cooh b c2h6 c c6h6 d hcn

Explanation:

Step1: Analyze CH₃COOH

Acetic acid ($CH_3COOH$) has a carbon - oxygen double bond in the carboxyl group ($-COOH$), so it does not have only single bonds.

Step2: Analyze C₂H₆

Ethane ($C_2H_6$) has only C - C and C - H single bonds. The structure is $H_3C - CH_3$.

Step3: Analyze C₆H₆

Benzene ($C_6H_6$) has a delocalized π - bond system due to its aromaticity, which is not a single - bond only structure.

Step4: Analyze HCN

Hydrogen cyanide ($HCN$) has a carbon - nitrogen triple bond ($C\equiv N$), so it does not have only single bonds.

Answer:

B. $C_2H_6$