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Hydrogen

Hydrogen is a chemical element; it has the symbol H and atomic number 1. It is the lightest and most abundant chemical element in the universe, constituting about 75% of all normal matter. Under standard conditions, hydrogen is a gas of diatomic molecules with the formula H2, called dihydrogen, or sometimes hydrogen gas, molecular hydrogen, or simply…

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1H
99.9855%
2H
0.0115%
3H
trace
Appearance
Colorless gas
Atomic number (Z)
1
Block
s-block

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Overview

History

Chemistry

Occurrence

Production and storage

Applications

Safety and precautions

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Map overview Semantic statistics

Hydrogen

Nodes427
Edges426
Triples266
Avg. degree2
Density0.004684
Components1

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Hydrogen

Top relations

related to Further reading · 30
Hydrogen → Cambridge, Chart, Climate, David, Eric, Fact, Fiction, Franklin Watts, Harvard University Press, ISBN, Island Press, Its Significance, Its Story, John, Joseph, Knolls Atomic Power Laboratory, Massachusetts, New York, Newton, Nuclides
related to External links · 15
Hydrogen → Basic, Berkeley, Burkhard Militzer, California, Drexel University, Georgia State University, High, HyperPhysics, Nottingham, The Periodic Table, Timothy Jones, University, Videos, Wavefunction, Wayback Machine
related to 19th century · 13
Hydrogen → According, By, Diatomic, Edward Daniel Clarke, François Isaac, H2, He, James Clerk Maxwell's, James Dewar, One, Rivaz, The Döbereiner's, These
related to Niche and evolving uses · 13
Hydrogen → Applications, Beyond, Coolant, Cryogenic, Dayton, E949, Food, Leak, Liquid H2, Ohio, Pure, Shielding, The
related to 20th century · 12
Hydrogen → Because, Bohr, Due, Earth, Gilbert, However, In, Lewis, LiH, Moers, Sun, The
related to Protons and acids · 12
Hydrogen → Brønsted, Even, H3O, H9O4, In, Lower, Lowry, Other, Otherwise, The, To, Under
related to Storage · 12
Hydrogen → BH3, For, H2, H2-equivalents, H3N, If H2, In, It, Liquefaction, More, The, These
related to Terrestrial · 10
Hydrogen → As, Australia, Despite, Earth's, Elemental, France, H2, It, Large, Mali
see also · 10
Hydrogen → Chemistry, Combined, EarthPyrolysis, Industrial, Molecular, Natural, Procedures, Technologies, Thermal, Using
related to Reactions of H2 · 9
Hydrogen → According, Although, Earth, H2, It, The, The H-H, These, They

Important terminology Word statistics

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Important terminology

gas h2 water used also compounds production produced energy proton form carbon reaction deuterium fuel molecules electron metals temperature low

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
Hydrogen1H99.9855%1.00infobox
Hydrogen2H0.0115%1.00infobox
Hydrogen3Htrace1.00infobox
HydrogenAppearanceColorless gas1.00infobox
HydrogenAtomic number (Z)11.00infobox
HydrogenBlocks-block1.00infobox
HydrogenBoiling point(H2) 20.271 K ​(−252.879 °C, ​−423.182 °F)1.00infobox
HydrogenCAS Number12385-13-6 1333-74-0 (H2)1.00infobox
HydrogenCovalent radius31±5 pm1.00infobox
HydrogenCritical point32.938 K, 1.2858 MPa1.00infobox
HydrogenCrystal structure​hexagonal (hP4)1.00infobox
HydrogenDensity (at STP)0.08988 g/L1.00infobox
HydrogenDiscovery and first isolationHenry Cavendish (1766)1.00infobox
HydrogenElectron configuration1s11.00infobox
HydrogenElectronegativityPauling scale: 2.201.00infobox
HydrogenElectrons per shell11.00infobox
HydrogenGroupgroup 1: hydrogen and alkali metals1.00infobox
HydrogenHeat of fusion(H2) 0.117 kJ/mol1.00infobox
HydrogenHeat of vaporization(H2) 0.904 kJ/mol1.00infobox
HydrogenIonization energies1st: 1312.0 kJ/mol1.00infobox
HydrogenLattice constantsa = 378.97 pm c = 618.31 pm (at triple point)1.00infobox
HydrogenMagnetic orderingdiamagnetic1.00infobox
HydrogenMain isotopes.mw-parser-output .isotopes-table{text-align:center;width:100%;border-collapse:collapse;margin:0;padding:0}.mw-parser-output .isotopes-table-headers>:not(:first-child){padding:0…1.00infobox
HydrogenMelting point(.mw-parser-output .template-chem2-su{display:inline-block;font-size:80%;line-height:1;vertical-align:-0.35em}.mw-parser-output .template-chem2-su>span{display:block;text-align:…1.00infobox
HydrogenMolar heat capacity14.418 J/(mol·K) (H) 28.836 J/(mol·K) (H2)1.00infobox
HydrogenMolar magnetic susceptibility−3.98×10−6 cm3/mol (298 K)1.00infobox
HydrogenNamed byAntoine Lavoisier (1783)1.00infobox
HydrogenNamingname means 'water-former' in Greek1.00infobox
HydrogenNatural occurrenceprimordial1.00infobox
HydrogenOxidation statescommon: −1, +11.00infobox

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