Search results
Results from the WOW.Com Content Network
Propane was first synthesized by the French chemist Marcellin Berthelot in 1857 during his researches on hydrogenation. Berthelot made propane by heating propylene dibromide (C 3 H 6 Br 2) with potassium iodide and water. [9] [10]: p. 9, §1.1 [11] Propane was found dissolved in Pennsylvanian light crude oil by Edmund Ronalds in 1864.
This process is called fusion and it can give out energy. In stars that undergo nuclear fusion, fuel consists of atomic nuclei that can release energy by the absorption of a proton or neutron. In most stars the fuel is provided by hydrogen, which can combine to form helium through the proton-proton chain reaction or by the CNO cycle. When the ...
Matter is made up by atoms (formed by protons and other subatomic particles). When the environment is right, atoms can join together and form molecules, which give rise to most materials studied in materials science. But certain environments, such as high temperatures, don't allow atoms to form molecules, as the environmental energy exceeds ...
This video clip shows a visualization of the three-dimensional structure of the Pillars of Creation. Closer view of one pillar. Pillars of Creation is a photograph taken by the Hubble Space Telescope of elephant trunks of interstellar gas and dust in the Eagle Nebula, in the Serpens constellation, some 6,500–7,000 light-years (2,000–2,100 pc; 61–66 Em) from Earth. [1]
Carbon can be produced in stars at least as massive as the Sun by fusion of three helium-4 nuclei: 4 He + 4 He + 4 He --> 12 C. This is the triple alpha process. In stars as massive as the Sun, carbon-12 is also converted to carbon-13 and then onto nitrogen-14 by fusion with protons. 12 C + 1 H --> 13 C + e +. 13 C + 1 H --> 14 N.
In the dense nebulae where stars are produced, much of the hydrogen is in the molecular (H 2) form, so these nebulae are called molecular clouds. [4] The Herschel Space Observatory has revealed that filaments, or elongated dense gas structures, are truly ubiquitous in molecular clouds and central to the star formation process. They fragment ...
Discover the latest breaking news in the U.S. and around the world — politics, weather, entertainment, lifestyle, finance, sports and much more.
produced by the various p–p branches is produced via branch I while p–p II produces 16.68 percent and p–p III 0.02 percent. [1] Since half the neutrinos produced in branches II and III are produced in the first step (synthesis of a deuteron), only about 8.35 percent of neutrinos come from the later steps (see below), and about 91.65 ...