Chemistry - CHEMICAL BONDING Question with Solution | TestHub

For ${\text{C}}_2{\text{H}}_4$ (Ethene), the structure is ${\text{H}}_2\text{C}={\text{CH}}_2$. It contains $4$ $\text{C}-\text{H}$ single bonds and $1$ $\text{C}=\text{C}$ double bond. A single bond is a $\sigma$ bond, and a double bond consists of $1$ $\sigma$ and $1$ $\pi$ bond. Total bonds: $5\sigma$ bonds and $1\pi$ bond. Thus, A matches IV.

For ${\text{C}}_2{\text{H}}_2$ (Ethyne), the structure is $\text{HC}\equiv \text{CH}$. It contains $2$ $\text{C}-\text{H}$ single bonds and $1$ $\text{C}\equiv \text{C}$ triple bond. A triple bond consists of $1$ $\sigma$ and $2$ $\pi$ bonds. Total bonds: $3\sigma$ bonds and $2\pi$ bonds. Thus, B matches I.

For ${\text{CH}}_4$ (Methane), the central carbon atom is bonded to $4$ hydrogen atoms via single bonds. Total bonds: $4\sigma$ bonds. Thus, C matches III.

For ${\text{NH}}_3$ (Ammonia), the central nitrogen atom is bonded to $3$ hydrogen atoms via single bonds and has $1$ lone pair of electrons. Total bonds: $3\sigma$ bonds and one lone pair. Thus, D matches II.

The correct matching is A-IV, B-I, C-III, D-II.

Answer: A-IV, B-I, C-III, D-II