Hydrogen

Is a tasteless, colorless, toxic free gas that is highly combustible. Hydrogen is found everywhere in our daily lives and is the main combustion source or fuel to keep the sun burning and heating our atmosphere. Its by-product is dihydrogen monoxide (water). Hydrogen is a diatomic molecule. Hydrogen is the most abundant element in the universe. Hydrogen has the atomic number 1. It has an atomic weight of 1.00794. There is 1 proton in each hydrogen atom. 90% of the visible universe is composed of hydrogen. The melting point of hydrogen is 13.81K or -259.34 Celsius. The boiling point of hydrogen is 20.28 K or -252.87 Celsius. The density of hydrogen is 0.00008988 grams per cubic centimeter and it is classified as a nonmetal in the periodic table. Hydrogen's oxidation state in covalent compounds is most commonly +1.
 * Hydrogen **



Hydrogen only has 1 electron in its outer shell.

Hydrogen is French for water-maker, from the Greek word hudor meaning "water" and gennen meaning to "generate".
 * What are the origins of the word Hydrogen?**


 * The chemical symbol of hydrogen is H. It is an element with atomic number 1, this means that 1 proton is found in the nucleus of hydrogen.
 * Hydrogen is the lightest, simplest and most commonly found chemical element in the Universe, making up around 75% of its elemental mass.
 * Hydrogen is found in large amounts in giant gas planets and stars, it plays a key role in powering stars through fusion reactions.
 * Hydrogen is one of two important elements found in water (H 2 O). Each molecule of water is made up of two hydrogen atoms bonded to one oxygen atom.
 * In 1766, during an acid metal reaction, Henry Cavendish first formally recognized hydrogen. In 1781 he also found that hydrogen produces water when burned. While Cavendish is usually given credit for the discovery of hydrogen as an element, it had been produced by earlier scientists who were unaware of hydrogen as a unique chemical element.
 * It wasn’t until a few years later (1783) that hydrogen was given its name. The word hydrogen comes from the Greek word hydro (meaning water) and genes (meaning creator).
 * Hydrogen gas has the molecular formula H 2 . At room temperature and under standard pressure conditions, hydrogen is a gas that is tasteless, odorless and colorless.
 * Hydrogen can exist as a liquid under high pressure and an extremely low temperature of 20.28 kelvin (−252.87°C, −423.17 °F). Hydrogen is often stored in this way as liquid hydrogen takes up less space than hydrogen in its normal gas form. Liquid hydrogen is also used as a rocket fuel.
 * Under extreme compression hydrogen can also make a transition to a state known as metallic hydrogen. Laboratory research into this area is ongoing as scientists continue efforts to produce metallic hydrogen at low temperature and static compression.
 * Hydrogen is used to power a range of new alternate fuel vehicles. The chemical energy of hydrogen is converted by a combustion method similar to current engines or in a fuel cell which produces water and electricity by reacting hydrogen with oxygen.
 * Engineers and car manufacturers are researching the possibility of using hydrogen gas as an efficient and viable car fuel. One of the possibilities involves storing hydrogen as a solid state in car fuel tanks. While there are many challenges involved in this process it would allow for greater hydrogen storage in vehicles, allowing them to travel for longer before refueling.
 * Hydrogen peroxide is a chemical compound with the molecular formula H 2 O 2 . It is often used as a hair bleach or cleaner. At certain concentrations it can also be used to clean wounds.
 * Hydrogen was used for air travel from 1852 when the first hydrogen lifted airship was created by Henri Giffard. Later airships that used hydrogen were called zeppelins and while they were reliable and safe for the majority of the time their use was stopped soon after the Hindenburg disaster in 1937. The Hindenburg airship was destroyed in a midair fire over New Jersey that was both filmed and broadcast live on radio.
 * Hydrogen is commonly used in the petroleum and chemical industries and is also widely used for many physics and engineering applications such as welding or as a coolant.
 * Hydrogen can be potentially dangerous to humans due to fires that can start when it is mixed with air, our inability to breathe it in its pure oxygen free form and also in its extremely cold liquid state.

Hydrogen (H 2 ) the lightest element, has a gaseous specific gravity of 0.0695 and a boiling point of -423 F (-252.8 C) at atmospheric pressure. It is a colorless, odorless, tasteless, flammable gas found at concentrations of about 0.0001 % in air. Hydrogen is produced by several methods, including steam/methane reforming, dissociation of ammonia, and recovery from by-product streams from chemical manufacturing and petroleum reforming. Hydrogen can be stored and transported as either a gas a cryogenic liquid.

In the welding industry, hydrogen is used as a fuel in underwater oxy-hydrogen torches, and for metal welding and brazing. Hydrogen is widely used in petroleum refining processes such as hydrotreating, catalytic reforming, and hydro-cracking. It is used in the food industry for turning inedible grease into soaps and animal feeds. It is a raw material for innumerable chemical processes ranging from the manufacturing of high-density polyethylene and polypropylene resins to the hydrogenation of food-grade oils. Hydrogen is also used as a reducing gas in metals processing operations. Applications in the electronics industry are found in the manufacture of silicon wafers and computer chips. Rocket engine fuel is another major use for hydrogen since weight and energy considerations are paramount to its success.
 * __DOT Information__**


 * DOT Name:** Hydrogen


 * DOT Hazard Class:** Flammable Gas


 * DOT Label:** Flammable Gas


 * DOT ID No.:** UN1049


 * CAS No.:** 1333-74-0


 * Valve Outlet:** CGA 350, LB-CGA 110/170
 * Physical** **State** **in High Pressure Cylinder:** Gas


 * Toxicity:** Non-toxic


 * Fire Potential:** Flammable
 * __Physical Properties of Oxygen__**


 * Formula:** H 2


 * Molecular Weight:** 2.016 lb/mol


 * Specific Volume at 70°F and 1 atm:** 192.0 ft3/lb (11.99 m3/kg)


 * Specific Heat:** 6.87 BTU/lbmol-deg F@ 70 deg. F


 * Specific Gravity:** 0.069


 * Gas Density:** 0.005210 lb/ ft3 @ 70 deg. F. 14.7 PSIA


 * Boiling Point:** Temperature: -423.0 deg. F (-252.8 deg. C)

Liquid Density: 4.43 lb./ft3

Latent Heat: 95.0 BTU/lb.


 * Critical Point****:** Temperature: -400.3 deg. F

Pressure: 187.51 PSIA


 * Melting Point:** Temperature: -434.8 deg. F

Pressure: 1.021 PSIA

Discovered in 1766, the hydrogen atom is the simplest atom that can possibly exist. The most common isotope is composed of a single proton and an electron. There is relatively little hydrogen gas in the earth’s atmosphere, but there are plenty of hydrogen atoms in compounds like water. Consider that every molecule of water in all the seas, lakes and streams contains two hydrogen atoms; hydrogen is one of the ten most abundant elements on the earth. Hydrogen is a light colorless gas, which has no smell or taste when pure. It burns explosively in air or oxygen to form water, H 2 O. It combines directly with nonmetals to form compounds. With reactive metals such as lithium, sodium, and calcium, hydrogen forms metal hydrides. These decompose in water and liberate hydrogen gas. The cation H +, is characteristic of acids in aqueous solution. The principal industrial sources of hydrogen are: There are three isotopes of hydrogen: 1. 1H, occurs in nature at 99.9985% abundance, 2. 2H, or D, also known as //deuterium// or //heavy hydrogen// occurs in nature at 0.015% abundance, and 3. 3H, or T, also known as //tritium//, are found only in trace amounts. The most common compound is deuterium oxide, D 2 O, or //heavy water//. This name is appropriate because the deuterium atom is twice as heavy as 1H. Since deuterium occurs naturally, in every 7000 molecules of ordinary H 2 O, there is one D 2 O. Heavy water can be prepared by prolonged electrolysis of ordinary water. Approximately 100,000 gallons of water have to be carefully electrolyzed to produce a single gallon of pure heavy water. Considering the cost of the electrical energy involved in such a process, heavy water is generally regarded as a scarce commodity. Heavy water is a suitable and convenient moderator in nuclear reactors.
 * Electrolysis of aqueous solutions of sodium chloride, table salt.
 * reaction of carbon with water to form carbon monoxide and hydrogen gas,
 * cracking processes in oil refineries, and
 * Reaction of methane, CH 4 (in natural gas), or other simple hydrocarbons with steam.

Hydrogen provided the lift for the first reliable form of air travel, used in the airship invented by Henri Giffard, which evolved into airships (most notibly the Zepplin). This continued through World War I, until May 6th, 1937, the German airship, Hindenburg, burst into flames over New Jersey. Have you ever wondered why solid water (ice) floats on top of liquid water? Well it has something to do with hydrogen. Click this link to find out what's going on.
 * Interesting Fact About Hydrogen:**

Thermochemical
There are more than 200 thermochemical cycles which can be used for water splitting, around a dozen of these cycles such as the iron oxide cycle, cerium(IV) oxide-cerium(III) oxide cycle, zinc zinc-oxide cycle , sulfur-iodine cycle , copper-chlorine cycle and hybrid sulfur cycle are under research and in testing phase to produce hydrogen and oxygen from water and heat without using electricity. A number of laboratories (including in France, Germany, Greece, Japan, and the USA) are developing thermochemical methods to produce hydrogen from solar energy and water