Look up: Hydrogen

1. hydrogen
   The lightest and most abundant element. A hydrogen atom consists of one proton and one electron. A hydrogen nucleus is just a single proton. Hydrogen composes about 75 percent of the Sun but only a tiny fraction of the Earth.
   Found on http://antwrp.gsfc.nasa.gov/apod/lib/glo
   
   
2. hydrogen
   [n] - a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas
   Found on http://www.webdictionary.co.uk/definitio
   
   
3. Hydrogen
   Lightest of gases H2. Combined with oxygen = water, combined with carbon = hydrocarbons. Element H
   Found on http://www.encyclo.co.uk/visitor-contrib
   
   
4. Hydrogen
   The least dense element. It has metallic and non-metallic properties. The most abundant element in the universe. Hydrogen occurs as H₂ at ambient temperature and pressure, a colourless, odourless, and extremely flammable gas. In its free gaseous state it is only found in nature in small q...
   Found on http://www.diracdelta.co.uk/science/sour
   
   
5. Hydrogen
   H The lightest gaseous element, and simplest of all atoms, occurring rarely in nature as a single atom, but common in the form of water, and in all organic compounds
   Found on http://www.bio-power.co.uk/glossary.htm
   
   
6. Hydrogen
   Discovered : by Henry Cavendish in 1766Isolated in London, UKOrigin : The name is derived from the Greek ‘hydro genes`, meaning water forming.Description :A colourless, odourless gas that burns and can form an explosive mixture with air. It is currently manufactured from methane gas, but is al...
   Found on http://www.allchemicals.info/index/actio
   
   
7. hydrogen
   (H) H; protium. Element 1, atomic weight 1.00797. The most abundant element in the universe. Hydrogen occurs as H₂ at ambient temperature and pressure, a colorless, odorless, and extremely flammable gas. Discovered in 1766 by Cavendish.
   Found on http://antoine.frostburg.edu/chem/senese
   
   
8. Hydrogen
   The simplest element. Atomic Number 1. Hydrogen gas has a specific gravity of 0.0694 (air = 1), so it is much lighter than air. Hydrogen is highly flammable, forming water upon combustion. Explosive limits are 4% to 75%
   Found on http://www.encyclo.co.uk/local/20747
   
   
9. Hydrogen
   The lightest known gas which has been, and still is, extensively used in airships and balloons. Its one great drawback is that it is highly inflammable and this undesirable characteristic has been the cause of many disasters. Because of this the heavier gas, helium, is more suitable for airship use.
   Found on http://www.aeroplanemonthly.com/glossary
   
   
10. Hydrogen
    The lightest of the chemical elements, gaseous, colourless, odour-less and tasteless.
    Found on http://www.gadsbywicks.co.uk/uploaded/38
    
    
11. Hydrogen
    Hydrogen: The most plentiful element in the universe and one present in all organic compounds. Hydrogen is a gas with an atomic number of 1 and the symbol H. Two isotopes of hydrogen -- deuterium and tritium -- have been used as tracers in metabolic studies. Tritium is a long-lived weak emitter of r...
    Found on http://www.medterms.com/script/main/art.
    
    
12. hydrogen
    chemical element:atomic number 1 Category: Chemistry
    Found on http://www.mijnwoordenboek.nl/definition
    
    
13. Hydrogen
    Hy'dro·gen noun [ Hydro- , 1 + -gen : confer French hydrogène . So called because water is generated by its combustion. See Hydra .] (Chemistry) A gaseous element, colorless, tasteless, and odorless, the lightest kno...
    Found on http://www.encyclo.co.uk/webster/H/76
    
    
14. hydrogen
    <chemistry, element> Hydrogen is a gas element which has an atomic number of 1 and an atomic weight of 1.0079. It combines with oxygen to form water (H20) and is present in all organic compounds. A few types of bacteria can metabolise atmospheric hydrogen (H2). Hydrogen gas itself is not poiso...
    Found on http://www.mondofacto.com/facts/dictiona
    
    
15. hydrogen
    (H) (hi´dro-jәn) a chemical element, atomic number 1, atomic weight 1.00797. It exists as the mass 1 isotope (protium, or light or ordinary hydrogen), mass 2 isotope (deuterium, heavy hydrogen), and mass 3 isotope (tritium). hydrogen cyanide an extremely...
    Found on http://www.encyclo.co.uk/local/21001
    
    
16. Hydrogen
    • (n.) A gaseous element, colorless, tasteless, and odorless, the lightest known substance, being fourteen and a half times lighter than air (hence its use in filling balloons), and over eleven thousand times lighter than water. It is very abundant, being an ingredient of water and of many othe...
    Found on http://thinkexist.com/dictionary/meaning
    
    
17. hydrogen
    a colourless, odourless, tasteless, flammable gaseous substance that is the simplest member of the family of chemical elements. The hydrogen atom has ... [102 related articles]
    Found on http://www.britannica.com/eb/a-z/h/88
    
    
18. hydrogen
    hydrogen 1. A colorless, odorless, flammable gas that combines chemically with oxygen to form water: the lightest of the known chemical elements. 2. A colorless, highly flammable gaseous element, the lightest of all gases and the most abundant element in the universe, used in the production of synth...
    Found on http://www.wordinfo.info/words/index/inf
    
    
19. Hydrogen
    The element from which protons are extracted for acceleration.
    Found on http://www-bdnew.fnal.gov/operations/acc
    
    
20. hydrogen
    (H) Type: Term Pronunciation: hī′drō-jen Definitions: 1. A gaseous element, atomic no. 1, atomic wt. 1.00794. 2. The molecular form (H₂) of the element. Synonyms: dihydrogen
    Found on http://www.medilexicon.com/medicaldictio
    
    
21. Hydrogen
    The element from which protons are extracted for acceleration.
    Found on http://www-bdnew.fnal.gov/operations/acc
    
    
22. hydrogen
    hydrogen (hī'drujun) [Gr.,=water forming], gaseous chemical element; symbol H; at. no. 1; at. wt. 1.00794; m.p. -259.14°C; b.p. -252.87°C; density 0.08988 grams per liter at STP; valence usually +1.Sections in this article:IntroductionThe Isotopes and FormsPropertiesSources and Com...
    Found on http://www.infoplease.com/ce6/sci/A08247
    
    
23. Hydrogen
    Hydrogen is a non-metallic gaseous element with the symbol H. In its free gaseous state it is only found in nature in small quantities issuing from crevices in volcanic districts or near petroleum wells. It exists in combination everywhere; as a constituent of water, of all plants and animals, and i...
    Found on http://www.probertencyclopaedia.com/brow
    
    
24. hydrogen
    Colourless, odourless, gaseous, non-metallic element, atomic number 1, relative atomic mass 1.00797. It is the lightest of all the elements and occurs on Earth, chiefly in combination with oxygen, as water. Hydrogen is the most abundant element in the universe, where it accounts for 93% of the total number of atoms and 76% of the total ...
    Found on http://www.talktalk.co.uk/reference/ency
    
    
25. hydrogen
    a gas.
    Found on http://www.kidseclipse.com/pages/glossar