Atomic mass, symbol and atomic number
hydrogen is a naturally occurring element with the element symbol H and the ordinal number 1. In the periodic table it stands with an atomic mass of 1.008 u in the 1st main group. The chemical element discovered by Henry Cavendish in 1766 is not radioactive and is in a gaseous state at room temperature.
|Year of discovery:||1766|
|Atomic mass:||1,008 u|
|Atomic radius:||25 pm|
|Covalent radius:||31 pm|
|Van der Waals radius:||120 pm|
|ionization:||1312 kJ / mol|
|molar volume:||11,42 · 10-6 m3/ mol|
|Melting point:||-259 ° C|
|Boiling point:||-252 ° C|
|Heat of fusion:||0.55 kJ / mol|
|Heat of vaporization:||0.90 kJ / mol|
|Thermal conductivity:||0.18 W|
Did you know that ...
- Hydrogen on Earth does not occur in the form of atomic hydrogen (H), but only as a bound molecule (H2)?
- Hydrogen in the universe is the most common element?
- elementary hydrogen has no neutron?
- Hydrogen was used as a balloon gas despite its slight danger of explosion?
- Hydrogen bombs release more energy than uranium-based atomic bombs?
- it is possible to detect hydrogen by means of the oxyhydrogen gas sample?
- Hydrogen was discovered as early as 1766 by the chemist Henry Cavendish?