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Ozone is lost by reaction with atomic oxygen (plus other trace atoms). The ozone–oxygen cycle is the process by which ozone is continually regenerated in Earth's stratosphere, converting ultraviolet radiation (UV) into heat. In 1930 Sydney Chapman resolved the chemistry involved. The process is commonly called the Chapman cycle by atmospheric ...
[1] [2] Ozone is also an important constituent of the stratosphere, where the ozone layer (2 to 8 parts per million ozone) exists which is located between 10 and 50 kilometers above the Earth's surface. [3] The troposphere extends from the ground up to a variable height of approximately 14 kilometers above sea level.
The excess kinetic energy heats the stratosphere when the O atoms and the molecular oxygen fly apart and collide with other molecules. This conversion of UV light into kinetic energy warms the stratosphere. The oxygen atoms produced in the photolysis of ozone then react back with other oxygen molecule as in the previous step to form more ozone.
Since typical values of Λ are on the order of 10-100 pm, this is almost always an excellent approximation. When considering a set of N non-interacting but identical atoms or molecules, when Q T ≫ N , or equivalently when ρ Λ ≪ 1 where ρ is the density of particles, the total translational partition function can be written
Aerobic organisms use atmospheric dioxygen as the terminal oxidant in cellular respiration in order to obtain chemical energy. The ground state of dioxygen is known as triplet oxygen, 3 [O 2], because it has two unpaired electrons. The first excited state, singlet oxygen, 1 [O 2], has no unpaired electrons and is metastable.
There is evidence that tiny quantities of cyclic ozone exist at the surface of magnesium oxide crystals in air. [3] Cyclic ozone has not been made in bulk, although at least one researcher has attempted to do so using lasers. [4] Another possibility to stabilize this form of oxygen is to produce it inside confined spaces, e.g., fullerene. [5]
The term transmutation dates back to alchemy.Alchemists pursued the philosopher's stone, capable of chrysopoeia – the transformation of base metals into gold. [3] While alchemists often understood chrysopoeia as a metaphor for a mystical or religious process, some practitioners adopted a literal interpretation and tried to make gold through physical experimentation.
The reverse reaction, the addition of singlet oxygen to water, typically does not occur in part due to the scarcity of singlet oxygen. In biological systems, however, ozone is known to be generated from singlet oxygen, and the presumed mechanism is an antibody-catalyzed production of trioxidane from singlet oxygen. [2]