Termine preferito
Helium
Definizione
Una spiegazione completa del significato inteso di un concetto- 1. Chemical element, inert gas of Group 18 (noble gases) of the periodic table. The second lightest element (only hydrogen is lighter), helium is a colourless, odourless, and tasteless gas that becomes liquid at −268.9 °C (−452 °F). The boiling and freezing points of helium are lower than those of any other known substance. Helium is the only element that cannot be solidified by sufficient cooling at normal atmospheric pressure; it is necessary to apply pressure of 25 atmospheres at a temperature of 1 K (−272 °C, or −458 °F) to convert it to its solid form. atomic number ...(100 of 1077 words) (Brittanica). 2. Helium (from Greek: ἥλιος, romanized: helios, lit. 'sun') is a chemical element; it has symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table.[a] Its boiling point is the lowest among all the elements, and it does not have a melting point at standard pressures. It is the second-lightest and second most abundant element in the observable universe, after hydrogen. (Wikipedia)
Concetto più generale
Concetto più generaleIn altre lingue
Termini per il concetto in altre lingue- Helium
URI
https://purls.helmholtz-metadaten.de/skosmos/sdv/Helium