The structure of nitrous oxide (N2O) can best be described by a resonance of

two structures. The hybridization of nitrogen atoms in the two resonance

structures are:

both sp

one sp another sp3

both sp2

one sp another sp2

Nitrous oxide (N2O) features two main resonance structures: +N≡N−O−+N≡N−O− and N≡N+=O−N≡N+=O−. The hybridization of the nitrogen atoms across these structures is one sp and one sp2, making this the correct choice among the given options.

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Resonance Structures Overview

In the first structure (+N≡N−O−+N≡N−O−), the left nitrogen forms a triple bond (one sigma, two pi), giving it two electron domains for sp hybridization. The central nitrogen has one triple bond to the left N, one single bond to O, and a lone pair, totaling three domains for sp2 hybridization.

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The second structure (N≡N+=O−N≡N+=O−) reverses this: the left N is sp (triple bond), and the central N is sp2 (triple bond to left N, double bond to O). This mixed hybridization reflects the linear molecule’s electron delocalization.

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Option Explanations

• Both sp: Incorrect, as the central N in both structures has three electron domains (bonds plus lone pair), requiring sp2, not linear sp hybridization.

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• One sp another sp3: Wrong, since no N has four domains like sp3; the central N lacks a lone pair in a tetrahedral arrangement.

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• Both sp2: Invalid, because the terminal N in each structure has only two domains from the triple bond, fitting sp, not trigonal sp2.

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• One sp another sp2: Correct, matching the domain counts in both resonance forms for the two nitrogens.

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This resonance hybrid explains N2O’s bonding and properties like its use as an anesthetic.

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