Hydrogen has the # 1 atomic number in the periodic table, it is a nonmetal. It is 14 times lighter than air, meaning it rises and disperses very quickly (20 m / s).
A Hydrogen atom is unstable, so it combines with another atom to form a molecule ( H 2 ) and that is why only the latter can be found freely in nature.
Since its boiling point sits at 20.28 K (-252.87° C or -423.17° F), at ambient temperature it takes the state of gas.
Its melting point is of 13.81 K (-259.34 ° C or -434.81 ° F).
The sun uses H2 in a process known as fusion (this process has been studied for decades now and it is bound to become the replacement of nuclear fission). The atoms are crushed by immense pressure and heat to combine with each other, this releases an enormous amount of energy, which powers our star. It is estimated that there is enough H2 for the sun to run for another 5 billion years.
H 2 is non-corrosive, however, it can deteriorate certain metals affecting their mechanical properties.
Hydrogen has three common isotopes. The simplest isotope, called protium, is just ordinary hydrogen. The second, a stable isotope called deuterium, was discovered in 1932. The third isotope, tritium, was discovered in 1934.
Extremely flammable and explosive. Nevertheless, the auto-ignition temperature (point at which it will spontaneously ignite without the presence of a spark or flame) is equal to natural gas.
At standard temperature and pressure, H 2 is a colorless, tasteless, odorless gas. Completely undetectable by human senses, is non-toxic and non-poisonous but it is an asphyxiant.
It burns in a distinct blue color (given by the Sulphur content) at a velocity of 346 cm/s and it is almost imperceptible at daylight. If the gas' purity is high, it won't produce any smoke whatsoever.