Nitrous oxide NNO

Excess fertilizer and combustion processes also can increase nitrous oxide (NnO) and nitrogen oxides (NOx) in the atmosphere. Nitrous oxide is a powerful greenhouse gas, and nitrogen oxides lead to smog and acid rain. The production of fertilizers requires a great deal of energy. The use of fossil fuels to supply the thermal requirements for fertilizer production further increases emission of nitrogen compounds to the atmosphere. 

Dinitrogen oxide, nitrous oxide, N2O. Colourless gas, m.p. —9T C, b.p. —88-5°C (heat on NH4NO3). Decomposes to N2 and O2 above SOO C can be detonated. Linear molecule NNO. Used as a mild anaesthetic. 

Resonance occurs only between structures with the same arrangement of atoms. For example, although we might be able to write two hypothetical structures for the dinitrogen oxide (nitrous oxide) molecule, NNO and NON, there is no resonance between them, because the atoms lie in different locations. 

Nitrous oxide is a linear nonsymmetrical molecule, NNO. Its photochemistry has been investigated many times37. The known products of the photochemical decomposition of N20 are N2, 02, and NO. Two primary processes may be visualized... 

Nitrous oxide, N20 16 valence electrons. Here, two skeletons come to mind, NNO and NON. The structure NNO is suggested by chemical evidence and confirmed by spectral studies (Chap. 25). There are three distributions of electrons consistent with the octet rule ... 

The carbonyl sulfide calculations were not as straightforward as the 2D nitrous oxide work. One issue is that the transition involves three transition dipoles to various states, whereas in nitrous oxide the absorption is dominated by a single transition. The calculation for OCS only considered a single transition. In addition the quality of the potential energy surfaces was not as high, and the 2D approximation not as good, for OCS relative to NNO. An illustration of this is that the predicted OCS spectrum has a maximum at 214 nm while the experimental spectrum has a maximum at 223 nm. In comparison the difference in peak location for NNO was only 3 nm. 

Nitrous oxide, N2O. This molecule is linear and its electric dipole moment is close to zero (017 D). Because of the similar scattering powers of N and 0 it is not possible to distinguish by electron diffraction between the alternatives NNO and NON, but the former is supported by spectroscopic data. X-ray diffraction data... 

Predict the geometry of nitrous oxide, N2O, by the VSEPR method and draw resonance stmctures for the molecule. Hint The atoms are arranged as NNO.)... 

The molecule nitrous oxide NgO, contains just as many electrons as CO2. Hence, one would at first be inclined to expect that it too is rectilinear and symmetrical. The investigations of Plyler and Barker(i39), however, have shown conclusively that the molecule is rectilinear and unsymmetrical, very probably of the type NNO, although an unsymmetrical configuration NON cannot be excluded in principle. The rectilinear character is confirmed again by the simple type of rotational structure of all the vibration-rotation bands, already discussed in the case of diatomic molecules like HOI (see section 23 and fig. 33) and also found for CO2 (see previous section, fig. 43). That the molecule is unsymmetrical follows in the first place from the fact that all three normal frequencies ct>2, CO3 are active and, more generally, that the selection rule of Dennison for symmetrical triatomic molecules, according to which for the observable combination bands AtJg + A 3 must be odd, is not obeyed, in contrast to CO2. In addition, if... 

Draw three resonance structures for the molecule nitrous oxide, N2O (the atomic arrangement is NNO). Indicate formal charges. Rank the structures in their relative importance to the overall properties of the molecule. 

Fig. 1.37. Rotational Raman spectrum of nitrous oxide gas (NNO) run on the Cary Model 82 Raman spectrophotometer with argon ion 5145 A excitation. From Sloane, used with permission from The Society for Applied Spectroscopy.

---