Atomic radius/Å: 0.79
atomic volume/cm3/mol: 14.4
covalent radius/Å: 0.32
Electronic configuration: 1s1
ion radius/Å: 0.012
oxidation state: I
In 1766, in London, by h. Cavendish found.
In the most abundant element in the universe, the main and oxygen, water exists in the form of and nature, also exist in the mine, and oil, and steam in the well.
Used in the production of ammonia, ethanol, hydrogen, brominated hydrogen, vegetable oil and not saturated hydrocarbons of hydrogen, the rocket fuel, low temperature science research, etc. There are two isotopic: deuterium (D) and the majority (T).
State: tasteless, and a colourless, odourless, extremely easy burning gas. Melting point (℃) : 258.975
Boiling point (℃) : 252.732
Density (g/L / 273 K, 1 ATM) : 0.0899
Spontaneous combustion point / ℃ : 500
Than hot/J/gK: 14.304
Evaporation heat/KJ/mol: 0.44936
Melting hot/KJ/mol: 0.05868
Flash point / ℃ : 253
Coefficient of thermal conductivity: 0.001815
Abundance retention time/year:
The sun (relative to the H = 1 x 1012) : the most abundant element in sea water/P.P.M. : as the composition of water is present in sea water, also have some gas H2
The earth's crust/P.P.M. : 1520 dissolved in it.
Atmospheric/P.P.M. (volume) : 0.5
The human body the content in liver/P.P.M. : 93 000
Organs: muscle/P.P.M. : 93 000
Blood/mg dm-3: water is in the blood, intake:
Bone/P.P.M. : 52 000 people (70 Kg) are total body: 7 Kg
Hydrogen is the first of the periodic table element, the element name comes from the Greek, original intention is "water element". Hydrogen is made KaWenDiXu English chemist discovered in 1766, called the flammable air, and proved it in the air in the burning form water. In 1787, French chemist and tin hydrogen is a kind of elemental proof and name. Hydrogen in abundance in the crust is very high, according to the atoms 15.4%, but the weight just 1%. In the universe, hydrogen is the most abundant elements. On earth with chemical and state hydrogen mainly exists in water and organic matter. There are three kinds of isotope: Pie, deuterium, majority.
Hydrogen in usually conditions for colorless, odorless gas; Gas molecule consists of two atoms; Melting point-259.14 ° C, boiling point-252.8 ° C, the critical temperature 33.19 K, critical pressure 12.98 atmospheric pressure, the density of the gas 0.0899 g/l; Water solubility 21.4 cm ³ / kg water (0 ° C), slightly soluble in organic solvents.
At normal temperature, hydrogen is not active, but can be used to activate the right catalyst. Under high temperature, hydrogen is highly lively. In addition to the rare gas elements, almost all of the elements can and hydrogen generation compounds. Of nonmetal elements hydride usually called one of hydrogen, such as hydrogen, hydrogen sulfide and halogenating; Metal elements of the hydride called metal hydride, such as hydrogenated lithium, hydrogenated calcium.
Hydrogen is an important industrial raw material and energy source of the future.