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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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gas h2 water used also compounds production produced energy proton form carbon reaction deuterium fuel molecules electron metals temperature low
| Subject | Predicate | Object | Confidence | Src |
|---|---|---|---|---|
| Hydrogen | 1H | 99.9855% | 1.00 | infobox |
| Hydrogen | 2H | 0.0115% | 1.00 | infobox |
| Hydrogen | 3H | trace | 1.00 | infobox |
| Hydrogen | Appearance | Colorless gas | 1.00 | infobox |
| Hydrogen | Atomic number (Z) | 1 | 1.00 | infobox |
| Hydrogen | Block | s-block | 1.00 | infobox |
| Hydrogen | Boiling point | (H2) 20.271 K (−252.879 °C, −423.182 °F) | 1.00 | infobox |
| Hydrogen | CAS Number | 12385-13-6 1333-74-0 (H2) | 1.00 | infobox |
| Hydrogen | Covalent radius | 31±5 pm | 1.00 | infobox |
| Hydrogen | Critical point | 32.938 K, 1.2858 MPa | 1.00 | infobox |
| Hydrogen | Crystal structure | hexagonal (hP4) | 1.00 | infobox |
| Hydrogen | Density (at STP) | 0.08988 g/L | 1.00 | infobox |
| Hydrogen | Discovery and first isolation | Henry Cavendish (1766) | 1.00 | infobox |
| Hydrogen | Electron configuration | 1s1 | 1.00 | infobox |
| Hydrogen | Electronegativity | Pauling scale: 2.20 | 1.00 | infobox |
| Hydrogen | Electrons per shell | 1 | 1.00 | infobox |
| Hydrogen | Group | group 1: hydrogen and alkali metals | 1.00 | infobox |
| Hydrogen | Heat of fusion | (H2) 0.117 kJ/mol | 1.00 | infobox |
| Hydrogen | Heat of vaporization | (H2) 0.904 kJ/mol | 1.00 | infobox |
| Hydrogen | Ionization energies | 1st: 1312.0 kJ/mol | 1.00 | infobox |
| Hydrogen | Lattice constants | a = 378.97 pm c = 618.31 pm (at triple point) | 1.00 | infobox |
| Hydrogen | Magnetic ordering | diamagnetic | 1.00 | infobox |
| Hydrogen | Main 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… | 1.00 | infobox |
| Hydrogen | Melting 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:… | 1.00 | infobox |
| Hydrogen | Molar heat capacity | 14.418 J/(mol·K) (H) 28.836 J/(mol·K) (H2) | 1.00 | infobox |
| Hydrogen | Molar magnetic susceptibility | −3.98×10−6 cm3/mol (298 K) | 1.00 | infobox |
| Hydrogen | Named by | Antoine Lavoisier (1783) | 1.00 | infobox |
| Hydrogen | Naming | name means 'water-former' in Greek | 1.00 | infobox |
| Hydrogen | Natural occurrence | primordial | 1.00 | infobox |
| Hydrogen | Oxidation states | common: −1, +1 | 1.00 | infobox |
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