CHEMISTRY · Multi-part · CBSE · Chemistry · Chemical Bonding and Molecular Structure · Chemical Bonding and Molecular Structure
Problem
Dinitrogen tetroxide, N2O4, is an important component of some rocket propellants. Because its molecular formula allows more than one skeletal framework, careful electron-counting and formal-charge analysis are required to select the most plausible Lewis representation.
Respond fully to each item below.
(a) Compute the total number of valence electrons in one molecule of N2O4.
(b) Propose two distinct skeletal connectivities consistent with this formula and the octet rule (for example, differing in whether the nitrogen atoms are joined by a single bond or a double bond). Draw a complete Lewis diagram for each connectivity, showing all lone pairs.
(c) For each connectivity in part (b), generate all significant resonance forms that delocalize electron density onto the oxygen atoms. Depict the movement of electrons with curved arrows and label any non-zero formal charges.
(d) Using the resonance forms and formal-charge considerations developed in part (c), identify which skeletal connectivity is most strongly supported. Justify your choice in a concise paragraph.