Reactions of HydrogenReactions of Hydrogen through Active MetalsNatural Occurrence & Other Sources

Hydrogen is a colormuch less, odormuch less and tastemuch less gas that is the most plentiful element in the known universe. It is also the lightest (in terms of atomic mass) and the simplest, having only one proton and one electron (and no neutrons in its most widespread isotope). It is all approximately us. It is a component of water (H2O), fats, petroleum, table sugar (C6H12O6), ammonia (NH3), and also hydrogen peroxide (H2O2)—points essential to life, as we know it.

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Hydrogen Facts

Atomic Number: 1 Atomic Symbol: H Atomic Weight: 1.0079 Electronic Configuration: 1s1 Oxidation States: 1, -1 Atomic Radius: 78 pm Melting Point: -259.34°C Boiling Point: -252.87° C Elemental Classification: Non-Metal At Room Temperature: Colormuch less & Odormuch less Diatomic Gas

History of Hydrogen

Hydrogen comes from Greek interpretation “water producer” (“hydro” =water and also “gennao”=to make). First isolated and also determined as an element by Cavendish in 1766, hydrogen was believed to be many different things. Cavendish himself assumed that it was "inflammable air from metals", owing to its manufacturing by the activity of acids on steels. Before that, Robert Boyle and Paracelsus both offered reactions of iron and also acids to produce hydrogen gas and Antoine Lavoisier offered hydrogen its name bereason it produced water as soon as ignited in air. Others assumed it was pure phlogiston bereason of its flammcapability. Hydrogen is one of the ten most plentiful elements on the planet, however incredibly bit is found in elepsychological form as a result of its low thickness and retask. Much of the terrestrial hydrogen is locked up in water molecules and also organic compounds favor hydrocarbons.

Properties of Hydrogen

Hydrogen is a nonmetal and also is placed above team in the regular table bereason it has ns1 electron configuration prefer the alkali steels. However, it varies substantially from the alkali metals as it creates cations (H+) even more reluctantly than the various other alkali steels. Hydrogen‘s ionization energy is 1312 kJ/mol, while lithium (the alkali steel through the highest ionization energy) has an ionization power of 520 kJ/mol.

Since hydrogen is a nonmetal and develops H- (hydride anions), it is sometimes placed above the halogens in the routine table. Hydrogen also creates H2 dihydrogen prefer halogens. However before, hydrogen is very different from the halogens. Hydrogen has actually a much smaller sized electron affinity than the halogens.

H2 dihydrogen or molecular hydrogen is non-polar via two electrons. Tbelow are weak attrenergetic forces between H2 molecules, bring about low boiling and melting points. However, H2 has actually very strong intramolecular forces; H2 reactions are mostly slow-moving at room temperature due to strong H—H bond. H2 is conveniently triggered by warmth, irradiation, or catalysis. Activated hydrogen gas reacts very easily and also exothermically via many type of substances.

Hydrogen likewise has an capacity to form covalent bonds via a large range of substances. Since it provides strong O—H bonds, it is an excellent reducing agent for steel oxides. Example: CuO(s) + H2(g) → Cu(s) + H2O(g) H2(g) passes over CuO(s) to reduce the Cu2+ to Cu(s), while obtaining oxidized itself.

Reactions of Hydrogen

Hydrogen"s low ionization power renders it act favor an alkali metal:

However, it half-filled valence shell (through a (1s^1) configuration) with one (e^-) also causes hydrogen to act choose a halogen non-metal to gain noble gas configuration by adding a secondary electron

Reactions of Hydrogen through Active Metals

Hydrogen accepts e- from an active metal to develop ionic hydrides like LiH. By forming an ion with -1 charge, the hydrogen behaves favor a halogen.

Group 1 metals

<2M_(s)+H_2(g) ightarrow 2MH_(s)>

through (M) representing Group 1 Alkali steels


(2K_(s)+H_2(g) ightarrow 2KH_(s)) (2K_(s)+Cl_2(g) ightarrowhead 2KCl_(s))
Group 2 metals

via (M) representing Group 2 Alkaline Earth metals


(Ca_(s)+H_2(g) ightarrowhead CaH_2(s)) (Ca_(s)+Cl_2(g) ightarrowhead CaCl_2(s))

Reactions of Hydrogen with Nonmetals

Unlike metals creating ionic bonds via nonmetals, hydrogen forms polar covalent bonds. In spite of being electropositive prefer the energetic metals that form ionic bonds through nonsteels, hydrogen is a lot less electropositive than the active metals, and also creates covalent bonds.

Hydrogen + Halogen → Hydrogen Halide

Hydrogen gas reacting with oxygen to produce water and a large amount of heat: Hydrogen + Oxygen → Water

<(H_2(g)+O_2(g) ightarrow H_2O_(g)>

Uses & Application

The vast majority of hydrogen developed industrially today is made either from treatment of methane gas through heavy steam or in the manufacturing of "water gas" from the reaction of coal with vapor. Many of this hydrogen is used in the Haber procedure to manufacture ammonia.

Hydrogen is also supplied for hydrogecountry vegetable oils, turning them right into margarine and also shortening, and also some is supplied for liquid rocket fuel. Liquid hydrogen (unified through liquid oxygen) is a major component of rocket fuel (as pointed out over combination of hydrogen and oxygen relapses a vast amount of energy). Because hydrogen is a great reducing agent, it is offered to develop metals choose iron, copper, nickel, and also cobalt from their ores.

Due to the fact that one cubic feet of hydrogen can lift around 0.07 lbs, hydrogen lifted airships or Zeppelins became incredibly widespread in the beforehand 1900s.However, the usage of hydrogen for this objective was largely discontinued about World War II after the explosion of The Hindenburg; this prompted greater use of inert helium, fairly than flammable hydrogen for air take a trip.

Video Showing the explosion of The Hindenburg. (Video from Youtube)

Recently, because of the fear of fossil fuels running out, extensive research is being done on hydrogen as a resource of energy.Since of their moderately high energy densities liquid hydrogen and compressed hydrogen gas are possible fuels for the future.A huge benefit in utilizing them is that their combustion just produces water (it burns “clean”). However, it is exceptionally costly, and also not economically feasible via present innovation.

Combustion of fuel produces energy that have the right to be converted right into electrical power as soon as energy in the heavy steam transforms a wind turbine to drive a generator. However before, this is not very efficient because a good deal of energy is lost as warmth. The manufacturing of electricity utilizing voltaic cell deserve to yield more electrical energy (a form of usable energy). Voltaic cells that transcreate lutz-heilmann.infoical energy in fuels (favor H2 and CH4) are called fuel cells. These are not self-had and so are not taken into consideration batteries. The hydrogen cell is a form of fuel cell involving the reaction between H2(g) via O2(g) to develop liquid water; this cell is twice as reliable as the finest interior burning engine. In the cell (in basic conditions), the oxygen is lessened at the cathode, while the hydrogen is oxidized at the anode.

Reduction: O2(g)+2H2O(l)+4e- → 4OH-(aq)

Oxidation: H2(g) + 2OH-(aq) → 2H2O(l) + 2e-

Overall: 2H2(g) + O2(g) → 2H2O(l)

E°cell= Reduction- Oxidation= E°O2/OH- - E°H2O/H2 = 0.401V – (-0.828V) = +1.23

However before, this technology is far from being supplied in day-to-day life due to its great costs.

api/deki/files/1116/Isotopes.jpg?revision=1&size=bestfit&width=422&height=204" />Figure : Three Hydrogen Isotopes (Image Made by of Ridhi Sachdev) Protium (1H) is the most prevalent isotope, consisting of 99.98% of naturally arising hydrogen. It is a nucleus containing a single proton. Tritium (3H) consists of 2 neutrons in its nucleus and is radioenergetic through a 12.3-year half-life, which is continuously developed in the upper environment due to cosmic rays. It is have the right to also be made in a lab from Lithium-6 in a nuclear reactor. Tritium is additionally supplied in hydrogen bombs. It is extremely rare (around 1 in every 1,018 atoms) and is formed in the setting by cosmic ray bombardment. Most tritium is made by bombarding Li with neutrons. Tritium is offered in thermonuclear weapons and experimental fusion reactors.


Shultz, M., Kelly, M., Paritskies, L., Wagner, J. A Theme-Based Course: Hydrogen as the Fuel of the Future. Journal of lutz-heilmann.infoical Education 2009 86 (9), 105. Rigden, John. Hydrogen: The Essential Element. The President and also Fellows of Harvard College. 2003. Banks, Alton. Hydrogen. Journal of lutz-heilmann.infoical Education 1989 66 (10), 801. Petrucci, Ralph H. General lutz-heilmann.infoistry. ninth ed. Upper Saddle River: Prtempt Hall, 2007. Publish Sadava, Heller, Orians, Purves, Hillis. Life The Science of Biology. 8th ed. Sunderland, MA: W.H. Freeman, 2008. Dinga, G. Hydrogen:The ultimate fuel and also power carrier.

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Journal of lutz-heilmann.infoical Education 1988 65 (8), 688.

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Write the reactivity of Na(s) via H2(g). What is the name of the radioenergetic isotope of hydrogen? What attributes of alkali steels does hydrogen display? What attributes of halogens does hydrogen display? How does the electronegativity of hydrogen compare to that of the halogens? What is the electron configuration of a neutral hydrogen atom.


2Na(s) + H2(g)→ 2NaH(s) Tritium Hydrogen is inserted over group in the regular table because it has ns1 electron configuration favor the alkali steels. However before, it varies considerably from the alkali steels as it creates cations (H+) even more reluctantly than the various other alkali metals. Hydrogen‘s ionization energy is 1312 kJ/mol, while lithium (the alkali metal via the highest possible ionization energy) has actually an ionization energy of 520 kJ/mol. Due to the fact that hydrogen is a nonmetal and also forms H- (hydride anions), it is sometimes placed above the halogens in the routine table. Hydrogen also creates H2 dihydrogen choose halogens. However before, hydrogen is very different from the halogens. Hydrogen has actually a much smaller sized electron affinity than the halogens. Hydrogen is much less electronegative than the halogens. 1s1