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Nitrogen-13 and oxygen-15 are produced in the atmosphere when gamma rays (for example from lightning) knock neutrons out of nitrogen-14 and oxygen-16: 14 N + γ → 13 N + n 16 O + γ → 15 O + n. The nitrogen-13 produced as a result decays with a half-life of 9.965(4) min to carbon-13, emitting a positron.
Nitrogen-13 is used in medical PET imaging in the form of 13 N-labelled ammonia. It can be produced with a medical cyclotron, using a target of pure water with a trace amount of ethanol. The reactants are oxygen-16 (present as H 2 O) and a proton, and the products are nitrogen-13 and an alpha particle (helium-4). 1 H + 16 O → 13 N + 4 He
Oxygen-15 is a radioisotope, often used in positron emission tomography (PET). It can be used in, among other things, water for PET myocardial perfusion imaging and for brain imaging. [20] [21] It has an atomic mass of 15.003 0656 (5), and a half-life of 122.266(43) s. It is produced through deuteron bombardment of nitrogen-14 using a cyclotron ...
Examples include carbon-14, nitrogen-15, and oxygen-16 in the table above. Isobars are nuclides with the same number of nucleons (i.e. mass number) but different numbers of protons and neutrons. Isobars neighbor each other diagonally from lower-left to upper-right. Examples include carbon-14, nitrogen-14, and oxygen-14 in the table above.
All carbon atoms have 6 protons, but they can have either 6, 7, or 8 neutrons. Since the mass numbers of these are 12, 13 and 14 respectively, said three isotopes are known as carbon-12, carbon-13, and carbon-14 (12 C, 13 C, and 14 C). Natural carbon is a mixture of 12 C (about 98.9%), 13 C (about 1.1%) and about 1 atom per trillion of 14 C.
[7] [8] This conclusion arose from a belief that is now known to be mistaken, that the abundance of nitrogen in the sun is approximately 10%; it is actually less than half a percent. [15] The CN-cycle, named as it contains no stable isotope of oxygen, involves the following cycle of transformations: [15] 12 6 C → 13 7 N → 13 6 C → 14 7 N
Liquid nitrogen is one of the "coolest" things to experiment with and there are many videos of tests that show how a variety of materials react when they get in touch with it.
Beryllium + Oxygen: 23.9 [3] Lithium + Fluorine: 23.75 [citation needed] Octaazacubane potential explosive: 22.9 [4] Hydrogen + Oxygen: 13.4 [5] Gasoline + Oxygen –> Derived from Gasoline: 13.3 [citation needed] Dinitroacetylene explosive - computed [citation needed] 9.8: Octanitrocubane explosive: 8.5 [6] 16.9 [7] Tetranitrotetrahedrane ...