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  2. Oxygen - Wikipedia

    en.wikipedia.org/wiki/Oxygen

    The common allotrope of elemental oxygen on Earth is called dioxygen, O 2, the major part of the Earth's atmospheric oxygen (see Occurrence). O 2 has a bond length of 121 pm and a bond energy of 498 kJ/mol. [42] O 2 is used by complex forms of life, such as animals, in cellular respiration. Other aspects of O 2 are covered in the remainder of ...

  3. Bond energy - Wikipedia

    en.wikipedia.org/wiki/Bond_energy

    In chemistry, bond energy (BE) is one measure of the strength of a chemical bond. It is sometimes called the mean bond, bond enthalpy, average bond enthalpy, or bond strength. [1] [2] [3] IUPAC defines bond energy as the average value of the gas-phase bond-dissociation energy (usually at a temperature of 298.15 K) for all bonds of the same type ...

  4. Triplet oxygen - Wikipedia

    en.wikipedia.org/wiki/Triplet_oxygen

    Under a molecular orbital theory framework, the oxygen-oxygen bond in triplet dioxygen is better described as one full σ bond plus two π half-bonds, each half-bond accounted for by two-center three-electron (2c-3e) bonding, to give a net bond order of two (1+2× ⁠ 1 / 2 ⁠), while also accounting for the spin state (S = 1).

  5. Singlet oxygen - Wikipedia

    en.wikipedia.org/wiki/Singlet_oxygen

    The energy difference of 94.3 kJ/mol between ground state and singlet oxygen corresponds to a forbidden singlet-triplet transition in the near-infrared at ~1270 nm. [12] As a consequence, singlet oxygen in the gas phase is relatively long lived (54-86 milliseconds), [ 13 ] although interaction with solvents reduces the lifetime to microseconds ...

  6. Dioxygenyl - Wikipedia

    en.wikipedia.org/wiki/Dioxygenyl

    It is formally derived from oxygen by the removal of an electron: O 2 → O + 2 + e −. The energy change for this process is called the ionization energy of the oxygen molecule. Relative to most molecules, this ionization energy is very high at 1175 kJ/mol. [1] As a result, the scope of the chemistry of O +

  7. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    Connect the atoms by single bonds. Each oxygen must be bonded to the nitrogen, which uses four electrons—two in each bond. Place lone pairs. The 14 remaining electrons should initially be placed as 7 lone pairs. Each oxygen may take a maximum of 3 lone pairs, giving each oxygen 8 electrons including the bonding pair.

  8. Molecular orbital theory - Wikipedia

    en.wikipedia.org/wiki/Molecular_orbital_theory

    Atomic orbitals must also overlap within space. They cannot combine to form molecular orbitals if they are too far away from one another. Atomic orbitals must be at similar energy levels to combine as molecular orbitals. Because if the energy difference is great, when the molecular orbitals form, the change in energy becomes small.

  9. Binding energy - Wikipedia

    en.wikipedia.org/wiki/Binding_energy

    Bond energy and bond-dissociation energy are measures of the binding energy between the atoms in a chemical bond. It is the energy required to disassemble a molecule into its constituent atoms. This energy appears as chemical energy, such as that released in chemical explosions, the burning of chemical fuel and biological processes. Bond ...