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{{Element | name=Hydrogen | symbol=H | anumber=1 | amass=1.001 amu | noe=1 | class=Gas| cstructure=Unknown | color=Unknown |  }}

{{Element | name=Hydrogen | symbol=H | anumber=1 | amass=1.001 amu | noe=1 | class=Gas| cstructure=Unknown | color=Unknown |  }}

'''Hydrogen''' has the [[atomic symbol]] H and the [[atomic number]] of 1. Hydrogen is the most abundant of all the chemical elements, the [[universe]] is composed of roughly 75% hydrogen. However naturally occurring elemental hydrogen on [[Earth]] is extremely rare.

'''Hydrogen''' is the most abundant of all the [[element]]s,<ref>Hydrogen makes up roughly 75% of the matter in the [[universe]].</ref> and has the [[chemical symbol]] H and an [[atomic number]] of 1. Despite this abundance, naturally occurring elemental hydrogen is extremely rare on [[Earth]].

==Composition of the Atom==

==Composition of the atom==

One [[isotope]] of the hydrogen [[atom]] is made up of one [[proton]] and one [[electron]] with no [[neutron]]s. This is called [[protium]].  There is also [[deuterium]], with one proton, one electron, and one neutron, and [[tritium]] with one proton, one electron and TWO neutrons. Tritium is [[radioactive]].

Hydrogen [[atom]]s normally consist of a single [[proton]] and [[electron]], with no [[neutron]]. Other [[isotopes]] are formed as the atom gains neutrons: [[deuterium]] (one neutron) and [[tritium]] (two neutrons). Tritium is [[radioactive]].

==Compounds==

==Compounds==

Hydrogen can be found in both [[organic]] and [[inorganic]] compounds (for example, [[hydrocarbon]]s and metal hydrides, respectively.  Scientists have determined that hydrogen is the most common element in the universe.  It is an important component of [[water]].

Hydrogen can be found in both [[organic]] and [[inorganic]] compounds.<ref>For example, [[hydrocarbon]]s and metal hydrides, respectively</ref> It is an important component of [[water]].

==Fuel for Vehicles==

==Fuel for vehicles==

Hydrogen is a principal component of [[fuel cell]]s, which have the potential to be a major form of alternative energy in the future. Fuel cells are very clean energy sources; the only by-products of its use are [[water]] and heat. Since no [[pollutant]]s or [[greenhouse gas]]ses are produced the use of fuel cells could provide cleaner air and potentially slow down [[global warming]].

Hydrogen is a principal component of [[fuel cell]]s, which have the potential to be a major form of alternative energy in the future. Fuel cells are very clean energy sources; their only by-products are [[water]] and heat. Since no [[pollutant]]s or [[greenhouse gas]]es are produced, the use of fuel cells could provide cleaner air and potentially slow down [[global warming]].

There are, however, some obstacles to overcome before hydrogen is a viable fuel source. One obstacle is that amount of hydrogen needed to fuel a regular sized car would be extremely large and would not be as convenient as a fuel tank is now. Hydrogen is extremely [[flammable]] and the flame is nearly invisible. The chances of a massive fatal explosion in an accident is greater than in one with [[gas]] powered vehicles.

Unfortunately, hydrogen is not a viable fuel source at present. Today's average car, for example, would require an unfeasibly large fuel tank to carry enough hydrogen for practical purposes. Hydrogen is also extremely [[flammable]] and suitable safeguards are needed to reduce the chances of a fatal explosion in an accident.  

If hydrogen could be used in cars, it would be important in establishing the [[hydrogen economy]].

If hydrogen could be used in cars, it would be important in establishing the [[hydrogen economy]].