Question

draw the most important lewis structure for the hocn molecule and then answer the following three questions. (note: hocn are bonded in order as written.) what is the ocn bond angle? 90° 109° 120° 180° how many σ and π bonds are there? three σ and one π three σ and two π four σ two σ and two π two σ and three π what is the valence bond description of the oxygen - carbon bond? σ(sp³o - sp²c) σ(sp³o - spc) σ(sp²o - sp³c) σ(sp²o - spc) σ(sp²o - spc) + π(2po - 2pc)

Explanation:

• OCN bond angle: In the Lewis structure of \(HOCN\), the central \(C\) atom bonded to \(O\) and \(N\) has a linear geometry (\(sp\) hybridization for \(C\) in the \(OCN\) part), so the bond angle is \(180^{\circ}\).
• \(\sigma\) and \(\pi\) bonds: The structure \(H - O - C\equiv N\) has \(H - O\) (\(\sigma\)), \(O - C\) (\(\sigma\)), \(C\equiv N\) (one \(\sigma\) and two \(\pi\)), total three \(\sigma\) and two \(\pi\) bonds.
• Oxygen - carbon bond description: \(O\) has \(sp^{2}\) hybridization (two lone pairs and one bond pair) and \(C\) (in \(O - C\equiv N\)) has \(sp\) hybridization. The \(\sigma\) bond is \(sp^{2}_{O}-sp_{C}\), and there is also a \(\pi\) bond (\(2p_{O}-2p_{C}\)) as part of the \(C\equiv N\) (but relevant to the \(O - C\) connection in terms of \(C\)'s hybridization affecting the overall bonding description for the \(O - C\) \(\sigma\) and the \(\pi\) contribution from \(C\)'s \(p\) orbitals).

Answer:

• OCN bond angle: \(180^{\circ}\)
• \(\sigma\) and \(\pi\) bonds: three \(\sigma\) and two \(\pi\)
• Valence bond description of the oxygen - carbon bond: \(\sigma(sp^{2}_{O}-sp_{C})+\pi(2p_{O}-2p_{C})\)