Hydrogen - New World Encyclopedia
Role in history of quantum theory Because of its relatively simple atomic structure, consisting only of a proton and an electron, the hydrogen atom, together with the spectrum of light produced from it or absorbed by it, has been central to the development of the theory of atomic structure. Etymology The term hydrogen (Latin: 'hydrogenium') can be traced to a combination of the ancient Greek words hydor, meaning "water," and genes, meaning "forming." This refers to the observation that when hydrogen burns, it produces water
Element, Chemical - humans, body, used, water, Earth, life, law, plants
The experimental definition of an element can be explained by using a second definition: an element is a substance in which all atoms are of the same kind. We know that early civilizations knew about and used these elements because of tools, weapons, and pieces of art that remain from the early periods of human history
So - to summarize, your question has two parts: the abundance of iron and silicon is greater than the heavier elements in the universe in general, and the earth is at the right distance from the Sun so that when it condensed out of the solar nebula, the ligher elements were either bound up in compounds or blown away to the farther reaches of the solar system.Click Here to return to the search form. Back to the early solar nebula: In the center of this swirling gas cloud, or nebula, the density and temperature got high enough for a star to form and begin thermonuclear reactions in its core and shine
Massive stars (greater than five times the mass of the Sun): When their hydrogen becomes depleted, high mass stars convert helium atoms into carbon and oxygen, followed by the fusion of carbon and oxygen into neon, sodium, magnesium, sulfur and silicon. When these old, large stars with depleted cores supernova, they create heavy elements (all the natural elements heavier than iron) and spew them into space, forming the basis for life
Luminosity classes: two-dimensional classification Although temperature reigns supreme in defining the spectrum of a star, the density of the gas in the region where the absorption lines are formed plays a role too. When we look at the spectrum from the hot source after it has gone through the low- density gas, we therefore see narrow gaps at particular wavelengths where the light is diminished or even gone altogether
Mendeleev's formulation was clearly superior in several respects to the work of contemporary classifiers: it was the clearest, most consistent, and most systematic formulation, and Mendeleev made several testable predictions based on it. Therefore, in the study of compounds, not only the quantities and properties of the elements and their reciprocal behavior is to be taken into consideration, but also the atomic weight of the elements
Periodic Table of Elements - Elements Database
Mendeleev's Periodic Table It was only in 1869 when Dmitri Mendeleev, an inventor and chemist of Russian origin, discovered the Periodic Law and organized all chemical elements in columns and rows. Origins of the Periodic Table of Elements The Periodic Table displays all known chemical elements which are grouped by chemical properties and atomic structure
Stellar iron is actually denser than terrestrial iron, but the electrons have been stripped from all the atoms and the nuclei are not held together in a lattice. Those of around 8 solar masses will have hot enough cores to further ignite the carbon and fuse it into heavier elements such as oxygen, neon, and magnesium
assuming we get fusion reactors working within the next decade or so we will be converting mass amounts of hydrogen into helium, every country every continent. It would be released to the atmosphere when the natural gas is burnt.So, not filling a balloon with helium would not slow down (or speed up) the depletion of helium from the underground reservoirs
WMAP Big Bang Elements Test
One second after the Big Bang, the temperature of the universe was roughly 10 billion degrees and was filled with a sea of neutrons, protons, electrons, anti-electrons (positrons), photons and neutrinos. The important prediction that the cosmic microwave background (CMB) exists, and has a blackbody spectrum with a temperature of about 5 degrees above absolute zero, was a by-product of this work
Helium, Chemical Element - Overview, Discovery and naming, Physical properties, Chemical properties, Occurrence in nature, Isotopes
KEEP IT UP!3EDFDec 4, 2008 @ 7:19 pmWOW! That was an AMAZING article! It really helped me with my research for an essay! THANKS TO THE CREATOR!4EDFDec 18, 2008 @ 5:17 pmthat artical got me a WONDERFUL grade on my essay. helium comes from five large underground regions: the Hugoton Field that lies beneath Kansas, Oklahoma, and Texas; the Keyes Field in Oklahoma; the Panhandle and Cliffside Fields in Texas; and the Ridley Ridge area in Wyoming
Only in the relatively recent past have people begun to recognize the dramatic role humans play as an essentially geological force on the surface of Earth, affecting large-scale conditions and processes. ESS1.A: THE UNIVERSE AND ITS STARS What is the universe, and what goes on in stars? The sun is but one of a vast number of stars in the Milky Way galaxy, which is one of a vast number of galaxies in the universe
In 1929 Karl Friedrich Bonhoeffer, a German physical chemist, and Paul Harteck, an Austrian chemist, on the basis of earlier theoretical work, showed that ordinary hydrogen is a mixture of two kinds of molecules, ortho-hydrogen and para-hydrogen. As a result of the different vapour pressures of para-hydrogen and ortho-hydrogen, these forms of hydrogen can be separated by low-temperature gas chromatography, an analytical process that separates different atomic and molecular species on the basis of their differing volatilities
Dalton also noted that in series of compounds, the ratios of the masses of the second element that combine with a given weight of the first element can be reduced to small whole numbers (the law of multiple proportions). Deuterium gas (2H2, often written D2), made up from deuterium, a heavy isotope of hydrogen, was discovered in 1931 by Harold Urey, a professor of chemistry at Chicago and California (both USA)
Lifting Power of Helium and Hydrogen and Rigid Airship Operations
2) While methane is a tried and true way to power your engines and generators, it is expensive, wasteful, and down-right dirty when you compare it with my own system. Reply Mike Dinsdale November 7, 2012 at 2:37 am In the design of the Trimorphic Disc Sail the issue of the expansion of the lifting gas be it helium or hydrogen is compensated for by the expansion of twelve segmented gas ballonets interconnected by hoses and small valves within a ring mesh array able to expand
The RSC makes no representations whatsoever about the suitability of the information contained in the documents and related graphics published on this Site for any purpose. Here's Brian Clegg.Brian CleggForget 10 Downing Street or 1600 Pennsylvania Avenue, the most prestigious address in the universe is number one in the periodic table, hydrogen
It was once so hot that the Universe was filled with nearly equal amount of matter and antimatter: protons and antiprotons, neutrons and antineutrons, electrons and positrons, neutrinos and antineutrinos, and of course photons (which are their own antiparticle), among others. The brain just fills in a bunch of details because it decided that event took much longer than it really did, and therefore you should have been able to see a lot more than you normally would
In the laboratory, hydrogen can be produced by the action of acids on metals such as zinc or magnesium, or by the electrolysis of water (shown on the left). He showed the resulting (hydrogen) gas only burned if air was present and that a fraction of the air (we would now call it oxygen) was consumed by the burning.(4) Hydrogen was first recognized as a distinct element in 1766 by English scientist Henry Cavendish, when he prepared it by reacting hydrochloric acid with zinc
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