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| name |
Helium |
| latin |
Helium |
| french |
Hélium |
| german |
Helium |
| symbol |
He |
| proton number |
2 |
| atomic weight |
4.002602 |
| Pauling electronegativity |
- |
| electronic configuration |
1s2 |
| melting point |
0.95 K, -272.2°C, -457.96°F |
| boiling point |
4.22 K, -268.93°C, -452.07°F |
| group |
18 |
| period |
1 |
| state (by 20°C) |
gas |
| oxidation states |
- |
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|
Discoverer
| Year of discovery |
Discoverers |
| 1868 |
Pierre Janssen (1824-1907) |
| 1895 |
Sir William Ramsay (1852-1916) and independently Nils Abraham Langlet (1868-1936) and Per Teodor Cleve (1840-1905) |
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Czech version