Halogen

Source: Wikipedia, the free encyclopedia.
This article is about the chemical series. For other uses, see Halogen (disambiguation).
Halogens
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
chalcogens ←    → noble gases
IUPAC group number 17
Name by element fluorine group
Trivial name halogens
CAS group number
(US, pattern A-B-A)
 VIIA
old IUPAC number
(Europe, pattern A-B)
 VIIB
↓ Period
2
Image: Liquid fluorine at cryogenic temperatures
Fluorine (F)
9 Halogen
3
Image: Chlorine gas
Chlorine (Cl)
17 Halogen
4
Image: Liquid bromine
Bromine (Br)
35 Halogen
5
Image: Iodine crystal
Iodine (I)
53 Halogen
6 Astatine (At)
85 Halogen
7 Tennessine (Ts)
117 Halogen

Legend

primordial element
element from decay
Synthetic
Atomic number color:
black=solid, green=liquid, red=gas

The halogens (

IUPAC nomenclature, this group is known as group 17.[5]

The word "halogen" means "salt former" or "salt maker". When halogens react with metals, they produce a wide range of salts, including calcium fluoride, sodium chloride (common table salt), silver bromide and potassium iodide.[6]

The group of halogens is the only

1 and 15, assuming white phosphorus is taken as the standard state.[n 1] All of the halogens form acids when bonded to hydrogen. Most halogens are typically produced from minerals or salts. The middle halogens—chlorine, bromine, and iodine—are often used as disinfectants. Organobromides are the most important class of flame retardants
, while elemental halogens are dangerous and can be toxic.

History

The fluorine mineral

George Gore, an English chemist, ran a current of electricity through hydrofluoric acid and probably produced fluorine, but he was unable to prove his results at the time.[citation needed] In 1886, Henri Moissan, a chemist in Paris, performed electrolysis on potassium bifluoride dissolved in anhydrous hydrogen fluoride, and successfully isolated fluorine.[7]

poisonous gas during World War I. It displaced oxygen in contaminated areas and replaced common oxygenated air with the toxic chlorine gas. The gas would burn human tissue externally and internally, especially the lungs, making breathing difficult or impossible depending on the level of contamination.[7]

Bromine was discovered in the 1820s by

French Academy changed the element's name to bromine.[7]

Iodine was discovered by

Joseph Gay-Lussac.[7]

In 1931,

Emilio G. Segrè, who bombarded bismuth with alpha particles.[7]

In 2010, a team led by nuclear physicist

JINR, Oak Ridge National Laboratory, Lawrence Livermore National Laboratory, and Vanderbilt University successfully bombarded berkelium-249 atoms with calcium-48 atoms to make tennessine.[8]

Etymology

In 1811, the German chemist Johann Schweigger proposed that the name "halogen" – meaning "salt producer", from αλς [hals] "salt" and γενειν [genein] "to beget" – replace the name "chlorine", which had been proposed by the English chemist Humphry Davy.[9] Davy's name for the element prevailed.[10] However, in 1826, the Swedish chemist Baron Jöns Jacob Berzelius proposed the term "halogen" for the elements fluorine, chlorine, and iodine, which produce a sea-salt-like substance when they form a compound with an alkaline metal.[11][12]

The English names of these elements all have the ending -ine. Fluorine's name comes from the Latin word fluere, meaning "to flow", because it was derived from the mineral fluorite, which was used as a flux in metalworking. Chlorine's name comes from the Greek word chloros, meaning "greenish-yellow". Bromine's name comes from the Greek word bromos, meaning "stench". Iodine's name comes from the Greek word iodes, meaning "violet". Astatine's name comes from the Greek word astatos, meaning "unstable".[7] Tennessine is named after the US state of Tennessee.

Characteristics

Chemical

The halogens fluorine, chlorine, bromine, and iodine are

nonmetals; the chemical properties of the two heaviest group 17 members have not been conclusively investigated. The halogens show trends in chemical bond energy moving from top to bottom of the periodic table column with fluorine deviating slightly. It follows a trend in having the highest bond energy in compounds with other atoms, but it has very weak bonds within the diatomic F2 molecule. This means that further down group 17 in the periodic table, the reactivity of elements decreases because of the increasing size of the atoms.[13]

Halogen bond energies (kJ/mol)[14]
X X2 HX BX3 AlX3 CX4
F 159 574 645 582 456
Cl 243 428 444 427 327
Br 193 363 368 360 272
I 151 294 272 285 239

Halogens are highly

organofluorine
compound), extremely dry glass, or metals such as copper or steel, which form a protective layer of fluoride on their surface.

The high reactivity of fluorine allows some of the strongest bonds possible, especially to carbon. For example, Teflon is fluorine bonded with carbon and is extremely resistant to thermal and chemical attacks and has a high melting point.

Molecules

Diatomic halogen molecules

The stable halogens form

molecules
. Due to relatively weak intermolecular forces, chlorine and fluorine form part of the group known as "elemental gases".

halogen molecule structure model d(X−X) / pm
(gas phase)		 d(X−X) / pm
(solid phase)
fluorine F2 143 149
chlorine Cl2 199 198
bromine Br2 228 227
iodine I2 266 272

The elements become less reactive and have higher melting points as the atomic number increases. The higher melting points are caused by stronger London dispersion forces resulting from more electrons.

Compounds

Hydrogen halides
Main article:
Hydrogen halides

All of the halogens have been observed to react with hydrogen to form hydrogen halides. For fluorine, chlorine, and bromine, this reaction is in the form of:

H2 + X2 → 2HX

However, hydrogen iodide and hydrogen astatide can split back into their constituent elements.[15]

The hydrogen-halogen reactions get gradually less reactive toward the heavier halogens. A fluorine-hydrogen reaction is explosive even when it is dark and cold. A chlorine-hydrogen reaction is also explosive, but only in the presence of light and heat. A bromine-hydrogen reaction is even less explosive; it is explosive only when exposed to flames. Iodine and astatine only partially react with hydrogen, forming equilibria.[15]

All halogens form binary compounds with hydrogen known as the hydrogen halides:

weak acid.[16]

All of the hydrogen halides are irritants. Hydrogen fluoride and hydrogen chloride are highly acidic. Hydrogen fluoride is used as an industrial chemical, and is highly toxic, causing pulmonary edema and damaging cells.[17] Hydrogen chloride is also a dangerous chemical. Breathing in gas with more than fifty parts per million of hydrogen chloride can cause death in humans.[18] Hydrogen bromide is even more toxic and irritating than hydrogen chloride. Breathing in gas with more than thirty parts per million of hydrogen bromide can be lethal to humans.[19] Hydrogen iodide, like other hydrogen halides, is toxic.[20]

Metal halides
Main article: Metal halides

All the halogens are known to react with sodium to form sodium fluoride, sodium chloride, sodium bromide, sodium iodide, and sodium astatide. Heated sodium's reaction with halogens produces bright-orange flames. Sodium's reaction with chlorine is in the form of:

2Na + Cl2 → 2NaCl[15]

Iron reacts with fluorine, chlorine, and bromine to form iron(III) halides. These reactions are in the form of:

2Fe + 3X2 → 2FeX3[15]

However, when iron reacts with iodine, it forms only iron(II) iodide.

Fe + I2 → FeI2

Iron wool can react rapidly with fluorine to form the white compound iron(III) fluoride even in cold temperatures. When chlorine comes into contact with a heated iron, they react to form the black iron(III) chloride. However, if the reaction conditions are moist, this reaction will instead result in a reddish-brown product. Iron can also react with bromine to form iron(III) bromide. This compound is reddish-brown in dry conditions. Iron's reaction with bromine is less reactive than its reaction with fluorine or chlorine. A hot iron can also react with iodine, but it forms iron(II) iodide. This compound may be gray, but the reaction is always contaminated with excess iodine, so it is not known for sure. Iron's reaction with iodine is less vigorous than its reaction with the lighter halogens.[15]

Interhalogen compounds
Main article: Interhalogen

Interhalogen compounds are in the form of XYn where X and Y are halogens and n is one, three, five, or seven. Interhalogen compounds contain at most two different halogens. Large interhalogens, such as ClF3 can be produced by a reaction of a pure halogen with a smaller interhalogen such as ClF. All interhalogens except IF7 can be produced by directly combining pure halogens in various conditions.[21]

Interhalogens are typically more reactive than all diatomic halogen molecules except F2 because interhalogen bonds are weaker. However, the chemical properties of interhalogens are still roughly the same as those of

covalent gases. However, some interhalogens are liquids, such as BrF3, and many iodine-containing interhalogens are solids.[21]

Organohalogen compounds

Many synthetic

thyroxine. Organohalogens are also synthesized through the nucleophilic abstraction reaction.[22]

Polyhalogenated compounds

PBDEs, and perfluorinated compounds
(PFCs), as well as numerous other compounds.

Reactions

Reactions with water

Fluorine reacts vigorously with water to produce oxygen (O2) and hydrogen fluoride (HF):[23]

2 F2(g) + 2 H2O(l) → O2(g) + 4 HF(aq)

Chlorine has maximum solubility of ca. 7.1 g Cl2 per kg of water at ambient temperature (21 °C).[24] Dissolved chlorine reacts to form hydrochloric acid (HCl) and hypochlorous acid, a solution that can be used as a disinfectant or bleach:

Cl2(g) + H2O(l) → HCl(aq) + HClO(aq)

Bromine has a solubility of 3.41 g per 100 g of water,[25] but it slowly reacts to form hydrogen bromide (HBr) and hypobromous acid (HBrO):

Br2(g) + H2O(l) → HBr(aq) + HBrO(aq)

Iodine, however, is minimally soluble in water (0.03 g/100 g water at 20 °C) and does not react with it.[26] However, iodine will form an aqueous solution in the presence of iodide ion, such as by addition of potassium iodide (KI), because the triiodide ion is formed.

Physical and atomic

The table below is a summary of the key physical and atomic properties of the halogens. Data marked with question marks are either uncertain or are estimations partially based on periodic trends rather than observations.

Halogen Standard
u)[n 2][28]
 Melting point
(K) 		Melting point
(°C) 		Boiling point
(K)[29] 		Boiling point
(°C)[29] 		Density
(g/cm3at 25 °C)
Pauling
) 		First
kJ·mol−1
)		 Covalent radius
(pm)[30]
Fluorine 18.9984032(5) 53.53 −219.62 85.03 −188.12 0.0017 3.98 1681.0 71
Chlorine [35.446; 35.457][n 3] 171.6 −101.5 239.11 −34.04 0.0032 3.16 1251.2 99
Bromine 79.904(1) 265.8 −7.3 332.0 58.8 3.1028 2.96 1139.9 114
Iodine 126.90447(3) 386.85 113.7 457.4 184.3 4.933 2.66 1008.4 133
Astatine [210][n 4] 575 302 ? 610 ? 337 ? 6.2–6.5[31] 2.2 899.0[32] ? 145[33]
Tennessine [294][n 4] ? 623-823[34] ? 350-550[34] ? 883[34] ? 610[34] ? 7.1-7.3[34] - ? 743[35] ? 157[34]
Z Element No. of electrons/shell
9 fluorine 2, 7
17 chlorine 2, 8, 7
35 bromine 2, 8, 18, 7
53 iodine 2, 8, 18, 18, 7
85 astatine 2, 8, 18, 32, 18, 7
117 tennessine 2, 8, 18, 32, 32, 18, 7 (predicted)[36]
Boiling or sublimation temperature dependence for halogens at various pressures. The vertical bar indicates the melting point
Sublimation or boiling point (oC) of halogens at various pressures[37]
Tmelt (оС) −100.7 −7.3 112.9
log(P[Pa]) mmHg Cl2 Br2 I2
2.12490302 1 −118 −48.7 38.7
2.82387302 5 −106.7 −32.8 62.2
3.12490302 10 −101.6 −25 73.2
3.42593302 20 −93.3 −16.8 84.7
3.72696301 40 −84.5 −8 97.5
3.90305427 60 −79 −0.6 105.4
4.12490302 100 −71.7 9.3 116.5
4.42593302 200 −60.2 24.3 137.3
4.72696301 400 −47.3 41 159.8
5.00571661 760 −33.8 58.2 183
log(P[Pa]) atm Cl2 Br2 I2
5.00571661 1 −33.8 58.2 183
5.30674661 2 −16.9 78.8
5.70468662 5 10.3 110.3
6.00571661 10 35.6 139.8
6.30674661 20 65 174
6.48283787 30 84.8 197
6.6077766 40 101.6 215
6.70468662 50 115.2 230
6.78386786 60 127.1 243.5

Isotopes

Fluorine has one stable and naturally occurring

protactinium-231
. A total of eighteen isotopes of fluorine have been discovered, with atomic masses ranging from 13 to 31.

Chlorine has two stable and naturally occurring isotopes, chlorine-35 and chlorine-37. However, there are trace amounts in nature of the isotope chlorine-36, which occurs via spallation of argon-36. A total of 24 isotopes of chlorine have been discovered, with atomic masses ranging from 28 to 51.[7]

There are two stable and naturally occurring isotopes of bromine, bromine-79 and bromine-81. A total of 33 isotopes of bromine have been discovered, with atomic masses ranging from 66 to 98.

There is one stable and naturally occurring

iodine-127. However, there are trace amounts in nature of the radioactive isotope iodine-129, which occurs via spallation and from the radioactive decay of uranium in ores. Several other radioactive isotopes of iodine have also been created naturally via the decay of uranium. A total of 38 isotopes of iodine have been discovered, with atomic masses ranging from 108 to 145.[7]

There are no stable isotopes of astatine. However, there are four naturally occurring radioactive isotopes of astatine produced via radioactive decay of uranium, neptunium, and plutonium. These isotopes are astatine-215, astatine-217, astatine-218, and astatine-219. A total of 31 isotopes of astatine have been discovered, with atomic masses ranging from 191 to 227.[7]

There are no stable isotopes of tennessine. Tennessine has only two known synthetic radioisotopes, tennessine-293 and tennessine-294.

Production

From left to right: chlorine, bromine, and iodine at room temperature. Chlorine is a gas, bromine is a liquid, and iodine is a solid. Fluorine could not be included in the image due to its high reactivity, and astatine and tennessine due to their radioactivity.

Approximately six million metric tons of the fluorine mineral fluorite are produced each year. Four hundred-thousand metric tons of hydrofluoric acid are made each year. Fluorine gas is made from hydrofluoric acid produced as a by-product in phosphoric acid manufacture. Approximately 15,000 metric tons of fluorine gas are made per year.[7]

The mineral halite is the mineral that is most commonly mined for chlorine, but the minerals carnallite and sylvite are also mined for chlorine. Forty million metric tons of chlorine are produced each year by the electrolysis of brine.[7]

Approximately 450,000 metric tons of bromine are produced each year. Fifty percent of all bromine produced is produced in the

Herbert Dow. It is also possible to produce bromine by passing chlorine through seawater and then passing air through the seawater.[7]

In 2003, 22,000 metric tons of iodine were produced. Chile produces 40% of all iodine produced, Japan produces 30%, and smaller amounts are produced in Russia and the United States. Until the 1950s, iodine was extracted from kelp. However, in modern times, iodine is produced in other ways. One way that iodine is produced is by mixing sulfur dioxide with nitrate ores, which contain some iodates. Iodine is also extracted from natural gas fields.[7]

Even though astatine is naturally occurring, it is usually produced by bombarding bismuth with alpha particles.[7]

Tennessine is made by using a cyclotron, fusing berkelium-249 and calcium-48 to make tennessine-293 and tennessine-294.

Applications

Disinfectants

Both chlorine and bromine are used as

fabric bleaches, and chlorine-derived bleaches are used in the production of some paper
products.

Lighting

incandescent lightbulbs at the same wattage. The gas reduces the thinning of the filament and blackening of the inside of the bulb resulting in a bulb that has a much greater life. Halogen lamps glow at a higher temperature (2800 to 3400 kelvin) with a whiter colour than other incandescent bulbs. However, this requires bulbs to be manufactured from fused quartz rather than silica glass to reduce breakage.[38]

Drug components

In

lipid membranes and tissues. It follows that there is a tendency for some halogenated drugs to accumulate in adipose tissue
.

The chemical reactivity of halogen atoms depends on both their point of attachment to the lead and the nature of the halogen.

aliphatic
halogen groups, which can exhibit considerable chemical reactivity. For aliphatic carbon-halogen bonds, the C-F bond is the strongest and usually less chemically reactive than aliphatic C-H bonds. The other aliphatic-halogen bonds are weaker, their reactivity increasing down the periodic table. They are usually more chemically reactive than aliphatic C-H bonds. As a consequence, the most common halogen substitutions are the less reactive aromatic fluorine and chlorine groups.

Biological role

Fluoride anions are found in ivory, bones, teeth, blood, eggs, urine, and hair of organisms. Fluoride anions in very small amounts may be essential for humans.[40] There are 0.5 milligrams of fluorine per liter of human blood. Human bones contain 0.2 to 1.2% fluorine. Human tissue contains approximately 50 parts per billion of fluorine. A typical 70-kilogram human contains 3 to 6 grams of fluorine.[7]

Chloride anions are essential to a large number of species, humans included. The concentration of chlorine in the

dry weight of cereals is 10 to 20 parts per million, while in potatoes the concentration of chloride is 0.5%. Plant growth is adversely affected by chloride levels in the soil falling below 2 parts per million. Human blood contains an average of 0.3% chlorine. Human bone typically contains 900 parts per million of chlorine. Human tissue contains approximately 0.2 to 0.5% chlorine. There is a total of 95 grams of chlorine in a typical 70-kilogram human.[7]

Some bromine in the form of the bromide anion is present in all organisms. A biological role for bromine in humans has not been proven, but some organisms contain

organobromine compounds. Humans typically consume 1 to 20 milligrams of bromine per day. There are typically 5 parts per million of bromine in human blood, 7 parts per million of bromine in human bones, and 7 parts per million of bromine in human tissue. A typical 70-kilogram human contains 260 milligrams of bromine.[7]

Humans typically consume less than 100 micrograms of iodine per day. Iodine deficiency can cause

herring, lobsters, sunflower seeds, seaweed, and mushrooms. However, iodine is not known to have a biological role in plants. There are typically 0.06 milligrams per liter of iodine in human blood, 300 parts per billion of iodine in human bones, and 50 to 700 parts per billion of iodine in human tissue. There are 10 to 20 milligrams of iodine in a typical 70-kilogram human.[7]

Astatine, although very scarce, has been found in micrograms in the earth.[7] It has no known biological role because of its high radioactivity, extreme rarity, and has a half-life of just about 8 hours for the most stable isotope.

Tennessine is purely man-made and has no other roles in nature.

Toxicity

The halogens tend to decrease in toxicity towards the heavier halogens.[41]

Fluorine gas is extremely toxic; breathing in fluorine at a concentration of 25 parts per million is potentially lethal.

dental caries, range from 0.7 to 1.2 mg/L to avoid the detrimental effects of fluoride while at the same time reaping the benefits.[43] People with levels between normal levels and those required for skeletal fluorosis tend to have symptoms similar to arthritis.[7]

Chlorine gas is highly toxic. Breathing in chlorine at a concentration of 3 parts per million can rapidly cause a toxic reaction. Breathing in chlorine at a concentration of 50 parts per million is highly dangerous. Breathing in chlorine at a concentration of 500 parts per million for a few minutes is lethal. In addition, breathing in chlorine gas is highly painful because of its corrosive properties. Hydrochloric acid is the acid of chlorine, while relatively nontoxic, it is highly corrosive and releases very irritating and toxic hydrogen chloride gas in open air.[41]

Pure bromine is somewhat toxic but less toxic than fluorine and chlorine. One hundred milligrams of bromine is lethal.[7] Bromide anions are also toxic, but less so than bromine. Bromide has a lethal dose of 30 grams.[7]

Iodine is somewhat toxic, being able to irritate the lungs and eyes, with a safety limit of 1 milligram per cubic meter. When taken orally, 3 grams of iodine can be lethal. Iodide anions are mostly nontoxic, but these can also be deadly if ingested in large amounts.[7]

Astatine is

radioactive and thus highly dangerous, but it has not been produced in macroscopic quantities and hence it is most unlikely that its toxicity will be of much relevance to the average individual.[7]

Tennessine cannot be chemically investigated due to how short its half-life is, although its radioactivity would make it very dangerous.

Superhalogen

Main article: Superatom

Certain aluminium clusters have superatom properties. These aluminium clusters are generated as anions (Al−
n with n = 1, 2, 3, ... ) in helium gas and reacted with a gas containing iodine. When analyzed by mass spectrometry one main reaction product turns out to be Al
13I−
.[44] These clusters of 13 aluminium atoms with an extra electron added do not appear to react with oxygen when it is introduced in the same gas stream. Assuming each atom liberates its 3 valence electrons, this means 40 electrons are present, which is one of the magic numbers for sodium and implies that these numbers are a reflection of the noble gases.

Calculations show that the additional electron is located in the aluminium cluster at the location directly opposite from the iodine atom. The cluster must therefore have a higher electron affinity for the electron than iodine and therefore the aluminium cluster is called a superhalogen (i.e., the vertical electron detachment energies of the moieties that make up the negative ions are larger than those of any halogen atom).[45] The cluster component in the Al
13I−
 ion is similar to an iodide ion or a bromide ion. The related Al
13I−
2 cluster is expected to behave chemically like the triiodide ion.[46][47]

See also

Look up halogen in Wiktionary, the free dictionary.

Notes

  1. ^ This could also be the case for group 12, although copernicium's melting and boiling points are still uncertain.
  2. least significant figure(s) of the number prior to the parenthesized value (i.e., counting from rightmost digit to left). For instance, 1.00794(7) stands for 1.00794±0.00007, while 1.00794(72) stands for 1.00794±0.00072.[27]
  3. ^ The average atomic weight of this element changes depending on the source of the chlorine, and the values in brackets are the upper and lower bounds.[28]
  4. ^ a b The element does not have any stable nuclides, and the value in brackets indicates the mass number of the longest-lived isotope of the element.[28]

References

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  2. ^ "Halogen". Merriam-Webster.com Dictionary.
  3. ^ "Halogen". Dictionary.com Unabridged (Online). n.d.
  4. ^ Fricke, Burkhard [2007.12.??] Superheavy elements a prediction of their chemical and physical properties PDF | "Element 117" | www.researchgate.net | Retrieved - 2023.08.13 (20:58:??) -- yyyy.mm.dd (hh:mm:ss)
  5. ^ "halogen | Elements, Examples, Properties, Uses, & Facts | Britannica". www.britannica.com. Retrieved 2022-03-21.
  6. ^ "Chemical properties of the halogens - Group 17 - the halogens - Edexcel - GCSE Combined Science Revision - Edexcel". BBC Bitesize. Retrieved 2022-03-21.
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  9. ^ Schweigger, J.S.C. (1811). "Nachschreiben des Herausgebers, die neue Nomenclatur betreffend" [Postscript of the editor concerning the new nomenclature]. Journal für Chemie und Physik (in German). 3 (2): 249–255. On p. 251, Schweigger proposed the word "halogen": "Man sage dafür lieber mit richter Wortbildung Halogen (da schon in der Mineralogie durch Werner's Halit-Geschlecht dieses Wort nicht fremd ist) von αλς Salz und dem alten γενειν (dorisch γενεν) zeugen." (One should say instead, with proper morphology, "halogen" (this word is not strange since [it's] already in mineralogy via Werner's "halite" species) from αλς [als] "salt" and the old γενειν [genein] (Doric γενεν) "to beget".)
  10. S2CID 170337569
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  11. ^ In 1826, Berzelius coined the terms Saltbildare (salt-formers) and Corpora Halogenia (salt-making substances) for the elements chlorine, iodine, and fluorine. See: Berzelius, Jacob (1826). "Årsberättelser om Framstegen i Physik och Chemie" [Annual Report on Progress in Physics and Chemistry]. Arsb. Vetensk. Framsteg (in Swedish). 6. Stockholm, Sweden: P.A. Norstedt & Söner: 187. From p. 187: "De förre af dessa, d. ä. de electronegativa, dela sig i tre klasser: 1) den första innehåller kroppar, som förenade med de electropositiva, omedelbart frambringa salter, hvilka jag derför kallar Saltbildare (Corpora Halogenia). Desse utgöras af chlor, iod och fluor *)." (The first of them [i.e., elements], the electronegative [ones], are divided into three classes: 1) The first includes substances which, [when] united with electropositive [elements], immediately produce salts, and which I therefore name "salt-formers" (salt-producing substances). These are chlorine, iodine, and fluorine *).)
  12. ^ The word "halogen" appeared in English as early as 1832 (or earlier). See, for example: Berzelius, J.J. with A.D. Bache, trans., (1832) "An essay on chemical nomenclature, prefixed to the treatise on chemistry," The American Journal of Science and Arts, 22: 248–276 ; see, for example p. 263.
  13. ^ Page 43, Edexcel International GCSE chemistry revision guide, Curtis 2011
  14. ^ Greenwood & Earnshaw 1997, p. 804.
  15. ^ a b c d e Jim Clark (2011). "Assorted reactions of the halogens". Retrieved February 27, 2013.
  16. ^ Jim Clark (2002). "THE ACIDITY OF THE HYDROGEN HALIDES". Retrieved February 24, 2013.
  17. ^ "Facts about hydrogen fluoride". 2005. Archived from the original on 2013-02-01. Retrieved 2017-10-28.
  18. ^ "Hydrogen chloride". Retrieved February 24, 2013.
  19. ^ "Hydrogen bromide". Retrieved February 24, 2013.
  20. ^ "Poison Facts:Low Chemicals: Hydrogen Iodid". Retrieved 2015-04-12.
  21. ^
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  22. ISBN 9783211993224
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  23. ^ "The Oxidising Ability of the Group 7 Elements". Chemguide.co.uk. Retrieved 2011-12-29.
  24. ^ "Solubility of chlorine in water". Resistoflex.com. Retrieved 2011-12-29.
  25. ^ "Properties of bromine". bromaid.org. Archived from the original on December 8, 2007.
  26. ^ "Iodine MSDS". Hazard.com. 1998-04-21. Retrieved 2011-12-29.
  27. CODATA reference. National Institute of Standards and Technology
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  28. ^
    S2CID 95898322
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  34. ^ a b c d e f "How Much Do You Know About the Element Tennessine?". www.thoughtco.com. Retrieved November 12, 2021.
  35. ^ "WebElements Periodic Table » Tennessine » properties of free atoms". www.webelements.com. Retrieved November 12, 2021.
  36. ISBN 978-94-007-0210-3
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  37. ^ "Краткий справочник физико-химических величин Равделя, Л.: Химия, 1974 г. – 200 стр. \\ стр 67 табл. 24" (PDF).
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Further reading
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