Where Is the Halogen Family on the Periodic Table

Grouping of chemical elements

Halogens
Hydrogen Helium Lithium Glucinium 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 Silverish 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 Proper name by element fluorine group Picayune proper name halogens CAS group number (US, pattern A-B-A) VIIA sometime IUPAC number (Europe, pattern A-B) VIIB
↓ Period
2	Fluorine (F) 9 Halogen
3	Chlorine (Cl) 17 Halogen
4	Bromine (Br) 35 Halogen
five	Iodine (I) 53 Element of group vii
six	Astatine (At) 85 Halogen
7	Tennessine (Ts) 117 Halogen
Legend primordial chemical element element from decay Constructed Atomic number color: black=solid, green=liquid, red=gas
v t due east

The halogens (^{[1] [2] [3]}) are a group in the periodic table consisting of five or six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). The artificially created element 117, tennessine (Ts), may also be a halogen. In the modern IUPAC classification, this group is known equally group 17.

The name "halogen" ways "salt former". When halogens react with metals, they produce a broad range of salts, including calcium fluoride, sodium chloride (common table common salt), silver bromide and potassium iodide.

The group of halogens is the only periodic table group that contains elements in three of the main states of affair at standard temperature and pressure. All of the halogens form acids when bonded to hydrogen. Most halogens are typically produced from minerals or salts. The eye halogens—chlorine, bromine, and iodine—are often used as disinfectants. Organobromides are the near important grade of flame retardants, while elemental halogens are unsafe and tin can be toxic.

History [edit]

The fluorine mineral fluorospar was known as early as 1529. Early on chemists realized that fluorine compounds comprise an undiscovered element, just were unable to isolate information technology. In 1860, George Gore, an English pharmacist, ran a current of electricity through hydrofluoric acid and probably produced fluorine, but he was unable to prove his results at the fourth dimension. In 1886, Henri Moissan, a chemist in Paris, performed electrolysis on potassium bifluoride dissolved in anhydrous hydrogen fluoride, and successfully isolated fluorine.^[4]

Hydrochloric acid was known to alchemists and early chemists. Even so, elemental chlorine was non produced until 1774, when Carl Wilhelm Scheele heated hydrochloric acid with manganese dioxide. Scheele called the chemical element "dephlogisticated muriatic acid", which is how chlorine was known for 33 years. In 1807, Humphry Davy investigated chlorine and discovered that information technology is an actual element. Chlorine combined with hydrochloric acid, as well as sulfuric acrid in sure instances created chlorine gas which was a poisonous gas during World War I. It displaced oxygen in contaminated areas and replaced common oxygenated air with the toxic chlorine gas. In which the gas would burn down human tissue externally and internally, specially the lungs making breathing difficult or impossible depending on the level of contamination.^[four]

Bromine was discovered in the 1820s by Antoine Jérôme Balard. Balard discovered bromine by passing chlorine gas through a sample of brine. He originally proposed the name muride for the new element, but the French University changed the element'due south name to bromine.^[4]

Iodine was discovered by Bernard Courtois, who was using seaweed ash equally part of a process for saltpeter manufacture. Courtois typically boiled the seaweed ash with water to generate potassium chloride. Yet, in 1811, Courtois added sulfuric acrid to his procedure and found that his process produced purple fumes that condensed into black crystals. Suspecting that these crystals were a new element, Courtois sent samples to other chemists for investigation. Iodine was proven to exist a new element by Joseph Gay-Lussac.^[4]

In 1931, Fred Allison claimed to have discovered chemical element 85 with a magneto-optical machine, and named the element Alabamine, but was mistaken. In 1937, Rajendralal De claimed to accept discovered element 85 in minerals, and called the element dakine, simply he was likewise mistaken. An attempt at discovering element 85 in 1939 by Horia Hulubei and Yvette Cauchois via spectroscopy was too unsuccessful, every bit was an attempt in the same yr by Walter Minder, who discovered an iodine-like element resulting from beta decay of polonium. Element 85, now named astatine, was produced successfully in 1940 by Dale R. Corson, Thou.R. Mackenzie, and Emilio Grand. Segrè, who bombarded bismuth with alpha particles.^[4]

In 2010, a team led by nuclear physicist Yuri Oganessian involving scientists from the JINR, Oak Ridge National Laboratory, Lawrence Livermore National Laboratory, and Vanderbilt University successfully bombarded berkelium-249 atoms with calcium-48 atoms to make tennessine-294. As of 2021, it is the near recent chemical element to be discovered.

Etymology [edit]

In 1811, the German chemist Johann Schweigger proposed that the name "element of group vii" – meaning "salt producer", from αλς [als] "salt" and γενειν [genein] "to beget" – replace the name "chlorine", which had been proposed by the English chemist Humphry Davy.^[v] Davy's name for the element prevailed.^[6] However, in 1826, the Swedish chemist Businesswoman 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 metallic.^{[7] [viii]}

The names of the elements all have the ending -ine. Fluorine's name comes from the Latin word fluere, meaning "to catamenia", because it was derived from the mineral fluorite, which was used as a flux in metalworking. Chlorine's name comes from the Greek give-and-take chloros, meaning "greenish-xanthous". Bromine's name comes from the Greek word bromos, pregnant "stench". Iodine'south proper noun comes from the Greek word iodes, significant "violet". Astatine's name comes from the Greek word astatos, meaning "unstable".^[iv] Tennessine is named after the US state of Tennessee.

Characteristics [edit]

Chemical [edit]

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 testify trends in chemical bond energy moving from peak to lesser of the periodic table cavalcade with fluorine deviating slightly. It follows a trend in having the highest bail free energy in compounds with other atoms, simply it has very weak bonds inside the diatomic F_two molecule. This means that further downwardly grouping 17 in the periodic table, the reactivity of elements decreases because of the increasing size of the atoms.^[9]

Halogen bond energies (kJ/mol)^[ten]

X	X2	HX	BXthree	AlX3	CXfour
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 reactive, and every bit such can be harmful or lethal to biological organisms in sufficient quantities. This high reactivity is due to the high electronegativity of the atoms due to their loftier effective nuclear accuse. Because the halogens have seven valence electrons in their outermost energy level, they tin can gain an electron past reacting with atoms of other elements to satisfy the octet rule. Fluorine is the virtually reactive of all elements; it is the only element more electronegative than oxygen, it attacks otherwise-inert materials such as glass, and it forms compounds with the usually inert noble gases. It is a corrosive and highly toxic gas. The reactivity of fluorine is such that, if used or stored in laboratory glassware, information technology can react with glass in the presence of small amounts of water to class silicon tetrafluoride (SiF_iv). Thus, fluorine must be handled with substances such as Teflon (which is itself an organofluorine compound), extremely dry glass, or metals such as copper or steel, which form a protective layer of fluoride on their surface.

The loftier 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 chemic attacks and has a high melting point.

Molecules [edit]

Diatomic halogen molecules [edit]

The halogens form homonuclear diatomic molecules (not proven for astatine). Due to relatively weak intermolecular forces, chlorine and fluorine form part of the group known as "elemental gases".

element of group vii	molecule	structure	model	d(Ten−X) / pm (gas phase)	d(X−Ten) / pm (solid stage)
fluorine	Fii			143	149
chlorine	Cl2			199	198
bromine	Brtwo			228	227
iodine	I2			266	272

The elements get less reactive and take college melting points every bit the atomic number increases. The higher melting points are caused by stronger London dispersion forces resulting from more than electrons.

Compounds [edit]

Hydrogen halides [edit]

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

H_ii + X₂ → 2HX

Nonetheless, hydrogen iodide and hydrogen astatide can split up back into their constituent elements.^[11]

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

All halogens class binary compounds with hydrogen known as the hydrogen halides: hydrogen fluoride (HF), hydrogen chloride (HCl), hydrogen bromide (HBr), hydrogen iodide (Hi), and hydrogen astatide (Hat). All of these compounds form acids when mixed with water. Hydrogen fluoride is the only hydrogen halide that forms hydrogen bonds. Hydrochloric acid, hydrobromic acrid, hydroiodic acrid, and hydroastatic acid are all strong acids, but hydrofluoric acid is a weak acid.^[12]

All of the hydrogen halides are irritants. Hydrogen fluoride and hydrogen chloride are highly acidic. Hydrogen fluoride is used as an industrial chemic, and is highly toxic, causing pulmonary edema and dissentious cells.^[13] Hydrogen chloride is also a dangerous chemical. Breathing in gas with more than than fifty parts per one thousand thousand of hydrogen chloride can cause expiry in humans.^[fourteen] 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 exist lethal to humans.^[15] Hydrogen iodide, like other hydrogen halides, is toxic.^[xvi]

Metallic halides [edit]

All the halogens are known to react with sodium to class 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 class of:

2Na + Cl_two → 2NaCl ^[11]

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

2Fe + 3X₂ → 2FeX_three ^[11]

However, when atomic number 26 reacts with iodine, it forms only iron(II) iodide.

Iron+I₂→FeI_two

Fe 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 (3) chloride. However, if the reaction conditions are moist, this reaction will instead event in a reddish-brown product. Iron can likewise react with bromine to form iron(3) bromide. This compound is reddish-brownish in dry conditions. Iron'south reaction with bromine is less reactive than its reaction with fluorine or chlorine. A hot iron tin besides react with iodine, but information technology forms iron(2) iodide. This compound may be gray, simply the reaction is always contaminated with excess iodine, so it is not known for sure. Iron'due south reaction with iodine is less vigorous than its reaction with the lighter halogens.^[xi]

Interhalogen compounds [edit]

Interhalogen compounds are in the class of XY_n where X and Y are halogens and n is one, three, v, or seven. Interhalogen compounds contain at almost two unlike halogens. Large interhalogens, such every bit ClF_iii can be produced by a reaction of a pure halogen with a smaller interhalogen such as ClF. All interhalogens except IF_seven can be produced by directly combining pure halogens in various conditions.^[17]

Interhalogens are typically more reactive than all diatomic halogen molecules except F₂ considering interhalogen bonds are weaker. Yet, the chemic properties of interhalogens are still roughly the same as those of diatomic halogens. Many interhalogens consist of one or more atoms of fluorine bonding to a heavier halogen. Chlorine tin can bond with upwards to iii fluorine atoms, bromine can bail with upwards to five fluorine atoms, and iodine can bond with up to seven fluorine atoms. Most interhalogen compounds are covalent gases. Nevertheless, some interhalogens are liquids, such as BrF_three, and many iodine-containing interhalogens are solids.^[17]

Organohalogen compounds [edit]

Many synthetic organic compounds such as plastic polymers, and a few natural ones, contain halogen atoms; these are known every bit halogenated compounds or organic halides. Chlorine is by far the virtually abundant of the halogens in seawater, and the only one needed in relatively large amounts (equally chloride ions) past humans. For example, chloride ions play a key office in brain function by mediating the action of the inhibitory transmitter GABA and are also used past the body to produce stomach acid. Iodine is needed in trace amounts for the production of thyroid hormones such as thyroxine. Organohalogens are also synthesized through the nucleophilic abstraction reaction.

Polyhalogenated compounds [edit]

Polyhalogenated compounds are industrially created compounds substituted with multiple halogens. Many of them are very toxic and bioaccumulate in humans, and have a very wide application range. They include PCBs, PBDEs, and perfluorinated compounds (PFCs), as well as numerous other compounds.

Reactions [edit]

Reactions with h2o [edit]

Fluorine reacts vigorously with water to produce oxygen (O₂) and hydrogen fluoride (HF):^[18]

2 F₂(thousand) + 2 H_iiO(l) → O₂(chiliad) + four HF(aq)

Chlorine has maximum solubility of ca. 7.i g Cl₂ per kg of water at ambience temperature (21 °C).^[19] Dissolved chlorine reacts to form hydrochloric acid (HCl) and hypochlorous acid, a solution that can be used as a disinfectant or bleach:

Cl_two(g) + H_twoO(l) → HCl(aq) + HClO(aq)

Bromine has a solubility of iii.41 g per 100 g of h2o,^[xx] but it slowly reacts to class hydrogen bromide (HBr) and hypobromous acid (HBrO):

Br₂(g) + H₂O(l) → HBr(aq) + HBrO(aq)

Iodine, yet, is minimally soluble in water (0.03 k/100 one thousand water at 20 °C) and does not react with it.^[21] However, iodine will grade an aqueous solution in the presence of iodide ion, such as past add-on of potassium iodide (KI), because the triiodide ion is formed.

Concrete and diminutive [edit]

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 atomic weight (u)[n 1] [23]	Melting signal (Yard)	Melting point (°C)	Boiling indicate (K)[24]	Boiling point (°C)[24]	Density (g/cm3at 25 °C)	Electronegativity (Pauling)	Get-go ionization energy (kJ·mol−1)	Covalent radius (pm)[25]
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 2]	171.six	−101.5	239.11	−34.04	0.0032	three.sixteen	1251.ii	99
Bromine	79.904(1)	265.8	−vii.3	332.0	58.viii	iii.1028	2.96	1139.9	114
Iodine	126.90447(3)	386.85	113.7	457.4	184.iii	four.933	ii.66	1008.iv	133
Astatine	[210][n iii]	575	302	? 610	? 337	? 6.two–6.5[26]	ii.ii	? 887.seven	? 145[27]
Tennessine	[294][due north 4]	? 623-823[28]	? 350-550[28]	? 883[28]	? 610[28]	? vii.one-7.3[28]	-	? 743[29]	? 157[28]

Z	Chemical element	No. of electrons/beat out
9	fluorine	two, 7
17	chlorine	2, 8, 7
35	bromine	2, viii, 18, seven
53	iodine	ii, 8, 18, 18, 7
85	astatine	two, viii, eighteen, 32, 18, seven
117	tennessine	2, 8, eighteen, 32, 32, 18, 7 (predicted) [xxx]

Isotopes [edit]

Fluorine has one stable and naturally occurring isotope, fluorine-nineteen. However, there are trace amounts in nature of the radioactive isotope fluorine-23, which occurs via cluster decay of protactinium-231. A total of eighteen isotopes of fluorine have been discovered, with atomic masses ranging from xiv to 31.

Chlorine has 2 stable and naturally occurring isotopes, chlorine-35 and chlorine-37. Even so, there are trace amounts in nature of the isotope chlorine-36, which occurs via spallation of argon-36. A full of 24 isotopes of chlorine have been discovered, with atomic masses ranging from 28 to 51.^[4]

There are 2 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.

In that location is ane stable and naturally occurring isotope of iodine, 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 accept been discovered, with atomic masses ranging from 108 to 145.^[four]

There are no stable isotopes of astatine. Yet, in that location are iv naturally occurring radioactive isotopes of astatine produced via radioactive disuse of uranium, neptunium, and plutonium. These isotopes are astatine-215, astatine-217, astatine-218, and astatine-219. A full of 31 isotopes of astatine have been discovered, with atomic masses ranging from 191 to 227.^[iv]

Tennessine has but 2 known constructed radioisotopes, tennessine-293 and tennessine-294.

Production [edit]

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 loftier reactivity, and astatine and tennessine due to their radioactivity.

Approximately half dozen one thousand thousand metric tons of the fluorine mineral fluorite are produced each year. Four hundred-thousand metric tons of hydrofluoric acrid are made each twelvemonth. 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.^[4]

The mineral halite is the mineral that is most ordinarily mined for chlorine, simply the minerals carnallite and sylvite are likewise mined for chlorine. Forty one thousand thousand metric tons of chlorine are produced each yr by the electrolysis of alkali.^[4]

Approximately 450,000 metric tons of bromine are produced each year. 50 per centum of all bromine produced is produced in the United States, 35% in State of israel, and about of the remainder in Mainland china. Historically, bromine was produced by adding sulfuric acid and bleaching pulverization to natural brine. However, in modern times, bromine is produced by electrolysis, a method invented past Herbert Dow. It is also possible to produce bromine past passing chlorine through seawater and then passing air through the seawater.^[iv]

In 2003, 22,000 metric tons of iodine were produced. Chile produces forty% of all iodine produced, Japan produces 30%, and smaller amounts are produced in Russia and the Usa. Until the 1950s, iodine was extracted from kelp. Nonetheless, in modernistic times, iodine is produced in other means. One mode that iodine is produced is by mixing sulfur dioxide with nitrate ores, which contain some iodates. Iodine is also extracted from natural gas fields.^[4]

Even though astatine is naturally occurring, it is usually produced by bombarding bismuth with alpha particles.^[4]

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

Applications [edit]

Disinfectants [edit]

Both chlorine and bromine are used equally disinfectants for drinking water, swimming pools, fresh wounds, spas, dishes, and surfaces. They kill bacteria and other potentially harmful microorganisms through a process known every bit sterilization. Their reactivity is likewise put to utilize in bleaching. Sodium hypochlorite, which is produced from chlorine, is the active ingredient of near material bleaches, and chlorine-derived bleaches are used in the production of some paper products. Chlorine also reacts with sodium to create sodium chloride, which is table salt.

Lighting [edit]

Element of group vii lamps are a type of incandescent lamp using a tungsten filament in bulbs that accept small amounts of a halogen, such every bit iodine or bromine added. This enables the product of lamps that are much smaller than not-element of group vii incandescent lightbulbs at the same wattage. The gas reduces the thinning of the filament and blackening of the within of the seedling resulting in a bulb that has a much greater life. Element of group vii lamps glow at a higher temperature (2800 to 3400 kelvins) with a whiter color than other incandescent bulbs. Nevertheless, this requires bulbs to be manufactured from fused quartz rather than silica drinking glass to reduce breakage.^[31]

Drug components [edit]

In drug discovery, the incorporation of halogen atoms into a atomic number 82 drug candidate results in analogues that are usually more lipophilic and less water-soluble.^[32] Every bit a consequence, halogen atoms are used to better penetration through lipid membranes and tissues. Information technology follows that there is a tendency for some halogenated drugs to accumulate in adipose tissue.

The chemic reactivity of halogen atoms depends on both their signal of attachment to the lead and the nature of the halogen. Aromatic halogen groups are far less reactive than aliphatic halogen groups, which tin showroom 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-element of group vii bonds are weaker, their reactivity increasing down the periodic table. They are normally more chemically reactive than aliphatic C-H bonds. As a effect, the most mutual halogen substitutions are the less reactive effluvious fluorine and chlorine groups.

Biological role [edit]

Fluoride anions are found in ivory, bones, teeth, blood, eggs, urine, and hair of organisms. Fluoride anions in very minor amounts may be essential for humans.^[33] There are 0.five milligrams of fluorine per liter of man blood. Homo basic comprise 0.ii to one.two% fluorine. Homo tissue contains approximately fifty parts per billion of fluorine. A typical 70-kilogram human contains 3 to vi grams of fluorine.^[4]

Chloride anions are essential to a big 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 1000000. Human claret contains an average of 0.3% chlorine. Man os typically contains 900 parts per meg of chlorine. Homo tissue contains approximately 0.two to 0.5% chlorine. There is a full of 95 grams of chlorine in a typical 70-kilogram human being.^[iv]

Some bromine in the form of the bromide anion is present in all organisms. A biological role for bromine in humans has non been proven, but some organisms comprise organobromine compounds. Humans typically consume 1 to 20 milligrams of bromine per day. There are typically 5 parts per million of bromine in homo blood, 7 parts per one thousand thousand of bromine in man bones, and vii parts per million of bromine in human tissue. A typical lxx-kilogram homo contains 260 milligrams of bromine.^[4]

Humans typically consume less than 100 micrograms of iodine per 24-hour interval. Iodine deficiency tin can crusade intellectual disability. Organoiodine compounds occur in humans in some of the glands, especially the thyroid gland, as well equally the stomach, epidermis, and immune arrangement. Foods containing iodine include cod, oysters, shrimp, herring, lobsters, sunflower seeds, seaweed, and mushrooms. However, iodine is not known to accept a biological function in plants. There are typically 0.06 milligrams per liter of iodine in human blood, 300 parts per billion of iodine in human being basic, and l to 700 parts per billion of iodine in human tissue. In that location are x to twenty milligrams of iodine in a typical seventy-kilogram homo.^[4]

Astatine, although very scarce, has been found in micrograms in the world.^[4] It has no known biological role because of its loftier radioactive decay, farthermost rarity, and has a half-life of just about viii hours for the nearly stable isotope.

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

Toxicity [edit]

The halogens tend to subtract in toxicity towards the heavier halogens.^[34]

Fluorine gas is extremely toxic; breathing in fluorine at a concentration of 25 parts per million is potentially lethal. Hydrofluoric acid is as well toxic, being able to penetrate skin and cause highly painful burns. In addition, fluoride anions are toxic, but non every bit toxic as pure fluorine. Fluoride can be lethal in amounts of 5 to ten grams. Prolonged consumption of fluoride above concentrations of 1.five mg/L is associated with a gamble of dental fluorosis, an aesthetic condition of the teeth.^[35] At concentrations to a higher place 4 mg/L, there is an increased risk of developing skeletal fluorosis, a condition in which bone fractures become more than common due to the hardening of basic. Current recommended levels in water fluoridation, a mode to forbid 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.^[36] People with levels between normal levels and those required for skeletal fluorosis tend to have symptoms like to arthritis.^[4]

Chlorine gas is highly toxic. Breathing in chlorine at a concentration of 3 parts per million can rapidly crusade a toxic reaction. Breathing in chlorine at a concentration of 50 parts per one thousand thousand is highly dangerous. Animate in chlorine at a concentration of 500 parts per million for a few minutes is lethal. Breathing in chlorine gas is highly painful.^[34]

Pure bromine is somewhat toxic but less toxic than fluorine and chlorine. I hundred milligrams of bromine is lethal.^[4] Bromide anions are also toxic, only less and then than bromine. Bromide has a lethal dose of 30 grams.^[4]

Iodine is somewhat toxic, being able to irritate the lungs and eyes, with a safety limit of ane milligram per cubic meter. When taken orally, 3 grams of iodine tin be lethal. Iodide anions are mostly nontoxic, but these can also be deadly if ingested in large amounts.^[4]

Astatine is very radioactive and thus highly unsafe, but it has not been produced in macroscopic quantities and hence it is most unlikely that its toxicity will exist of much relevance to the average individual.^[4]

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

Superhalogen [edit]

Certain aluminium clusters have superatom properties. These aluminium clusters are generated equally anions (Al ⁻
_n with n = 1, 2, iii, ... ) in helium gas and reacted with a gas containing iodine. When analyzed past mass spectrometry one main reaction production turns out to exist Al
₁₃ I ⁻
.^[37] These clusters of 13 aluminium atoms with an actress electron added practice not announced to react with oxygen when it is introduced in the same gas stream. Assuming each atom liberates its three 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 bear witness that the additional electron is located in the aluminium cluster at the location directly opposite from the iodine cantlet. The cluster must therefore have a higher electron affinity for the electron than iodine and therefore the aluminium cluster is called a superhalogen (i.eastward., the vertical electron disengagement energies of the moieties that make upward the negative ions are larger than those of whatever element of group vii cantlet).^[38] The cluster component in the Al
₁₃ I ⁻
ion is like to an iodide ion or a bromide ion. The related Al
₁₃ I ⁻
_ii cluster is expected to behave chemically like the triiodide ion.^{[39] [40]}

See also [edit]

Expect upwards element of group vii in Wiktionary, the free dictionary.

• Element of group vii bond
• Halogen lamp
• Halogenation
• Interhalogen
• Pseudohalogen

Notes [edit]

1. ^ The number given in parentheses refers to the measurement uncertainty. This uncertainty applies to the least pregnant effigy(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 .^[22]
2. ^ 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.^[23]
3. ^ The element does not take any stable nuclides, and the value in brackets indicates the mass number of the longest-lived isotope of the element.^[23]
4. ^ The element does non have any stable nuclides, and the value in brackets indicates the mass number of the longest-lived isotope of the element.^[23]

References [edit]

1. ^ Jones, Daniel (2017) [1917]. Peter Roach; James Hartmann; Jane Setter (eds.). English Pronouncing Dictionary. Cambridge: Cambridge Academy Press. ISBN978-iii-12-539683-viii.
2. ^ "Halogen". Merriam-Webster Dictionary.
3. ^ "Halogen". Dictionary.com Unabridged. Random House.
4. ^ ^{a b c d e f g h i j grand l chiliad due north o p q r southward t u v w x} Emsley, John (2011). Nature's Building Blocks. ISBN978-0199605637.
5. ^ 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 (ii): 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, "element of group vii" (this give-and-take is not strange since [information technology's] already in mineralogy via Werner's "halite" species) from αλς [als] "salt" and the old γενειν [genein] (Doric γενεν) "to beget".)
6. ^ Snelders, H. A. Yard. (1971). "J. S. C. Schweigger: His Romanticism and His Crystal Electrical Theory of Matter". Isis. 62 (3): 328–338. doi:x.1086/350763. JSTOR 229946. S2CID 170337569.
7. ^ In 1826, Berzelius coined the terms Saltbildare (common 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 Study on Progress in Physics and Chemistry] (in Swedish). Vol. six. Stockholm, Sweden: P.A. Norstedt & Söner. p. 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 offset of them [i.due east., elements], the electronegative [ones], are divided into three classes: one) The first includes substances which, [when] united with electropositive [elements], immediately produce salts, and which I therefore proper name "salt-formers" (table salt-producing substances). These are chlorine, iodine, and fluorine *).)
8. ^ The discussion "halogen" appeared in English as early on as 1832 (or earlier). See, for instance: Berzelius, J.J. with A.D. Bache, trans., (1832) "An essay on chemic nomenclature, prefixed to the treatise on chemistry," The American Journal of Science and Arts, 22: 248–276 ; meet, for example p. 263.
9. ^ Page 43, Edexcel International GCSE chemistry revision guide, Curtis 2011
10. ^ Greenwood & Earnshaw 1997, p. 804. sfn error: no target: CITEREFGreenwoodEarnshaw1997 (assist)
11. ^ ^{a b c d e} Jim Clark (2011). "Assorted reactions of the halogens". Retrieved February 27, 2013.
12. ^ Jim Clark (2002). "THE ACIDITY OF THE HYDROGEN HALIDES". Retrieved February 24, 2013.
13. ^ "Facts about hydrogen fluoride". 2005. Archived from the original on 2013-02-01. Retrieved 2017-10-28 .
14. ^ "Hydrogen chloride". Retrieved February 24, 2013.
15. ^ "Hydrogen bromide". Retrieved February 24, 2013.
16. ^ "Toxicant Facts:Low Chemicals: Hydrogen Iodid". Retrieved 2015-04-12 .
17. ^ ^{a b} Saxena, P. B (2007). Chemistry Of Interhalogen Compounds. ISBN9788183562430 . Retrieved February 27, 2013.
18. ^ "The Oxidising Ability of the Group seven Elements". Chemguide.co.britain. Retrieved 2011-12-29 .
19. ^ "Solubility of chlorine in water". Resistoflex.com. Retrieved 2011-12-29 .
20. ^ "Properties of bromine". bromaid.org. Archived from the original on Dec 8, 2007.
21. ^ "Iodine MSDS". Hazard.com. 1998-04-21. Retrieved 2011-12-29 .
22. ^ "Standard Uncertainty and Relative Standard Uncertainty". CODATA reference. National Institute of Standards and Technology. Retrieved 26 September 2011.
23. ^ ^{a b c d} Wieser, Michael Eastward.; Coplen, Tyler B. (2011). "Atomic weights of the elements 2009 (IUPAC Technical Report)" (PDF). Pure Appl. Chem. 83 (ii): 359–396. doi:10.1351/PAC-REP-10-09-14. S2CID 95898322. Retrieved 5 December 2012.
24. ^ ^{a b} Lide, D. R., ed. (2003). CRC Handbook of Chemical science and Physics (84th ed.). Boca Raton, FL: CRC Press.
25. ^ Slater, J. C. (1964). "Atomic Radii in Crystals". Periodical of Chemical Physics. 41 (x): 3199–3205. Bibcode:1964JChPh..41.3199S. doi:10.1063/1.1725697.
26. ^ Bonchev, Danail; Kamenska, Verginia (1981). "Predicting the properties of the 113–120 transactinide elements". The Journal of Concrete Chemical science. 85 (9): 1177–86. doi:ten.1021/j150609a021.
27. ^ "Become Facts About the Element Astatine". world wide web.thoughtco.com . Retrieved November 12, 2021.
28. ^ ^{a b c d e f} "How Much Practice You Know Almost the Element Tennessine?website=www.thoughtco.com". Retrieved November 12, 2021.
29. ^ "WebElements Periodic Table » Tennessine » backdrop of free atoms". www.webelements.com . Retrieved Nov 12, 2021.
30. ^
31. ^ "The Halogen Lamp". Edison Tech Heart . Retrieved 2014-09-05 .
32. ^ Thomas, M. (2000). Medicinal Chemistry an Introduction. John Wiley & Sons, West Sussex, UK. ISBN978-0-470-02597-0.
33. ^ Fawell, J. "Fluoride in Drinking-water" (PDF). World Health Organisation. Retrieved 10 March 2016.
34. ^ ^{a b} Grey, Theodore (2010). The Elements. ISBN9781579128951.
35. ^ Fawell, J.; Bailey, 1000.; Chilton, J.; Dahi, E.; Fewtrell, L.; Magara, Y. (2006). "Guidelines and standards" (PDF). Fluoride in Drinking-water. Earth Health Arrangement. pp. 37–nine. ISBN978-92-4-156319-2.
36. ^ "CDC Statement on the 2006 National Inquiry Council (NRC) Report on Fluoride in Drinking H2o". Centers for Affliction Control and Prevention. July ten, 2013. Archived from the original on January ix, 2014. Retrieved August 1, 2013.
37. ^ Bergeron, D. E.; Castleman, A. Welford; Morisato, Tsuguo; Khanna, Shiv Due north. (2004). "Formation of Al₁₃I⁻: Evidence for the Superhalogen Graphic symbol of Al_thirteen". Science. 304 (5667): 84–seven. Bibcode:2004Sci...304...84B. doi:10.1126/science.1093902. PMID 15066775. S2CID 26728239.
38. ^ Giri, Santanab; Behera, Swayamprabha; Jena, Puru (2014). "Superhalogens as Building Blocks of Element of group vii-Gratis Electrolytes in Lithium-Ion Batteries†". Angewandte Chemie. 126 (fifty): 14136. doi:10.1002/ange.201408648.
39. ^ Ball, Philip (16 April 2005). "A New Kind of Alchemy". New Scientist.
40. ^ Bergeron, D. E.; Roach, P. J.; Castleman, A. Due west.; Jones, Northward. O.; Khanna, Due south. N. (2005). "Al Cluster Superatoms every bit Halogens in Polyhalides and as Alkaline Earths in Iodide Salts". Science. 307 (5707): 231–5. Bibcode:2005Sci...307..231B. doi:10.1126/science.1105820. PMID 15653497. S2CID 8003390.

Further reading [edit]

• Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2d ed.). Butterworth-Heinemann. ISBN978-0-08-037941-viii.

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Source: https://en.wikipedia.org/wiki/Halogen

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