Therefore, no matter how electrons are shared between the nitrogen and oxygen atoms, there is no way for nitrogen to have an octet. It will have seven electrons, assuming that the oxygen atom does satisfy the octet. Nitric oxide is a by-product of combustion reactions that occur in engines, like those in automobile engines and fossil fuel power plants.
It is also produced naturally during the electrical discharge of lightning during thunderstorms. Nitrogen dioxide is the chemical compound with the formula NO 2. Again, nitrogen dioxide does not follow the octet rule for one of its atoms, namely nitrogen.
There is persistent radical character on nitrogen because it has an unpaired electron. The two oxygen atoms in this molecule follow the octet rule.
Nitrogen dioxide is an intermediate in the industrial synthesis of nitric acid, millions of tons of which is produced each year. This is because the activation energy is high, higher than the energy available at ambient temperature and because of the already low concentration of NO.
The probability that 2 molecules of NO will collide with sufficient energy and the correct orientation to form molecular nitrogen and oxygen is very low. The rate of the reaction is very low, even though it is favored energetically. Now consider the dimerization of NO2 to form N2O4. In this case, the enthalpy of the reaction is small and negative and the Gibbs free energy is strongly influenced by entropy and temperature. Akahama, Y. Physical Review Letters 74, — Physical Review B 76, Sun, J.
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