هالوجين

(تم التحويل من Halogen)

الهالوجينات هى سلسلة كيميائية . وتتكون من العناصر الموجودة في المجموعة 17 والتى كانت تسمى قديما ( VII or VIIA ) من الجدول الدوري وهى : الفلور ، الكلور ، البروم ، اليود ، الأستاتين والأنون سيبتيوم . ويعنى أصل كلمة هالوجين بالإغريقية إلى مكون الملح .

Halogens
Element 1: هيدروجين (H), لافلز آخر
Element 2: هليوم (He), غاز نبيل
Element 3: ليثيوم (Li), Alkali metal
Element 4: بريليوم (Be), Alkaline earth metal
Element 5: بورون (B), Metalloid
Element 6: كربون (C), لافلز آخر
Element 7: نيتروجين (N), لافلز آخر
Element 8: أكسجين (O), لافلز آخر
Element 9: فلور (F), هالوجين
Element 10: نيون (Ne), غاز نبيل
Element 11: صوديوم (Na), Alkali metal
Element 12: مغنسيوم (Mg), Alkaline earth metal
Element 13: ألومنيوم (Al), فلز آخر
Element 14: سليكون (Si), Metalloid
Element 15: فسفور (P), لافلز آخر
Element 16: كبريت (S), لافلز آخر
Element 17: كلور (Cl), هالوجين
Element 18: أرگون (Ar), غاز نبيل
Element 19: پوتاسيوم (K), Alkali metal
Element 20: كالسيوم (Ca), Alkaline earth metal
Element 21: سكانديوم (Sc), فلز انتقالي
Element 22: تيتانيوم (Ti), فلز انتقالي
Element 23: ڤناديوم (V), فلز انتقالي
Element 24: كروم (Cr), فلز انتقالي
Element 25: منگنيز (Mn), فلز انتقالي
Element 26: حديد (Fe), فلز انتقالي
Element 27: كوبالت (Co), فلز انتقالي
Element 28: نيكل (Ni), فلز انتقالي
Element 29: نحاس (Cu), فلز انتقالي
Element 30: زنك (Zn), فلز انتقالي
Element 31: گاليوم (Ga), فلز آخر
Element 32: جرمانيوم (Ge), Metalloid
Element 33: زرنيخ (As), Metalloid
Element 34: سلنيوم (Se), لافلز آخر
Element 35: بروم (Br), هالوجين
Element 36: كريپتون (Kr), غاز نبيل
Element 37: روبيديوم (Rb), Alkali metal
Element 38: سترونشم (Sr), Alkaline earth metal
Element 39: إتريوم (Y), فلز انتقالي
Element 40: زركونيوم (Zr), فلز انتقالي
Element 41: نيوبيوم (Nb), فلز انتقالي
Element 42: مولبدنم (Mo), فلز انتقالي
Element 43: تكنيشيوم (Tc), فلز انتقالي
Element 44: روذنيوم (Ru), فلز انتقالي
Element 45: روديوم (Rh), فلز انتقالي
Element 46: پلاديوم (Pd), فلز انتقالي
Element 47: فضة (Ag), فلز انتقالي
Element 48: كادميوم (Cd), فلز انتقالي
Element 49: إنديوم (In), فلز آخر
Element 50: قصدير (Sn), فلز آخر
Element 51: أنتيمون (Sb), Metalloid
Element 52: تلوريوم (Te), Metalloid
Element 53: يود (I), هالوجين
Element 54: زينون (Xe), غاز نبيل
Element 55: سيزيوم (Cs), Alkali metal
Element 56: باريوم (Ba), Alkaline earth metal
Element 57: لنثانم (La), Lanthanoid
Element 58: سريوم (Ce), Lanthanoid
Element 59: پراسيوديميوم (Pr), Lanthanoid
Element 60: نيوديميوم (Nd), Lanthanoid
Element 61: پرومثيوم (Pm), Lanthanoid
Element 62: سماريوم (Sm), Lanthanoid
Element 63: يوروپيوم (Eu), Lanthanoid
Element 64: گادولينيوم (Gd), Lanthanoid
Element 65: تربيوم (Tb), Lanthanoid
Element 66: ديسپروسيوم (Dy), Lanthanoid
Element 67: هولميوم (Ho), Lanthanoid
Element 68: إربيوم (Er), Lanthanoid
Element 69: ثوليوم (Tm), Lanthanoid
Element 70: إتربيوم (Yb), Lanthanoid
Element 71: لوتتيوم (Lu), Lanthanoid
Element 72: هافنيوم (Hf), فلز انتقالي
Element 73: تنتالم (Ta), فلز انتقالي
Element 74: تنگستن (W), فلز انتقالي
Element 75: رنيوم (Re), فلز انتقالي
Element 76: اوزميوم (Os), فلز انتقالي
Element 77: إريديوم (Ir), فلز انتقالي
Element 78: پلاتين (Pt), فلز انتقالي
Element 79: ذهب (Au), فلز انتقالي
Element 80: زئبق (Hg), فلز انتقالي
Element 81: ثاليوم (Tl), فلز آخر
Element 82: رصاص (Pb), فلز آخر
Element 83: بزموت (Bi), فلز آخر
Element 84: پولونيوم (Po), Metalloid
Element 85: أستاتين (At), هالوجين
Element 86: رادون (Rn), غاز نبيل
Element 87: فرانسيوم (Fr), Alkali metal
Element 88: راديوم (Ra), Alkaline earth metal
Element 89: أكتينيوم (Ac), Actinoid
Element 90: ثوريوم (Th), Actinoid
Element 91: پروتاكتنيوم (Pa), Actinoid
Element 92: يورانيوم (U), Actinoid
Element 93: نپتونيوم (Np), Actinoid
Element 94: پلوتونيوم (Pu), Actinoid
Element 95: أمريكيوم (Am), Actinoid
Element 96: كوريوم (Cm), Actinoid
Element 97: بركليوم (Bk), Actinoid
Element 98: كاليفورنيوم (Cf), Actinoid
Element 99: أينشتاينيوم (Es), Actinoid
Element 100: فرميوم (Fm), Actinoid
Element 101: مندلڤيوم (Md), Actinoid
Element 102: نوبليوم (No), Actinoid
Element 103: لورنسيوم (Lr), Actinoid
Element 104: رذرفورديوم (Rf), فلز انتقالي
Element 105: دبنيوم (Db), فلز انتقالي
Element 106: سيبورگيوم (Sg), فلز انتقالي
Element 107: Bohrium (Bh), فلز انتقالي
Element 108: هاسيوم (Hs), فلز انتقالي
Element 109: Meitnerium (Mt)
Element 110: Darmstadtium (Ds)
Element 111: Roentgenium (Rg)
Element 112: كوپرنيكيوم (Cn), فلز انتقالي
Element 113: أنون‌تريوم (Uut)
Element 114: أنون‌كواديوم (Uuq)
Element 115: أنون‌پنتيوم (Uup)
Element 116: أنون‌هكسيوم (Uuh)
Element 117: أنون‌سپتيوم (Uus)
Element 118: أنون‌اوكتيوم (Uuo)
chalcogens  noble gases
رقم أيوپاك للمجموعة 17
الاسم حسب العنصر fluorine group
اسم شائع halogens
رقم كاس للمجموعة (US) VIIA
رقم أيوپاك القديم (الاوروپي) 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

جزيئات هذه العناصر ثنائية الذرة في حالتها الطبيعية . وتحتاج إلى إلكترون واحد لملئ غلافها الإلكتروني الأخير ، ولذا فإنها تميل لتكوين أيون سالب أحادى الشحنة . وهذا الأيون السالب يسمى بأيون الهاليد ، فالأملاح التى تحتوى الأيونات تسمى هاليدات .

الهالوجينات عالية النشاط الكيميائي . ولذا فإنها يمكن أن تكون مضرة للكائنات الحية. الكلور واليود يتم إستخدامها كمهطر في عديد من الإستخدامات مثل : ماء الشرب ، أحواض السباحة ، الجروح الحديثة ، الصحون ، السطوح .فلهما القدرة على قتل البكتريا والكائنات الدقيقة الأخرى التى قد تكون ضارة ، فيما يسمى بعملية التطهير . كما يتم إستخدام خاصية النشاط الكيميائي في عملية التبييض . الكلور هو المكون النشيط لمعظم مبيضات الأقمشة ويستخدم في معظم المنتجات الورقية .

يتحد أيون الهاليد مع ذرة هيدروجين لتكوين الأحماض الهيدرولية ( HF ، HCl ، HBr ، HI ) ، وهى سلسلة من الأحماض القوية . ( يمكن أن يوضع أيضا HAt حمض الهيدراستاتيك كان يجب أن يوضع معهم ولكن نظرا لأن ليس ثابت على الإطلاق من ناحية تحلل ألفا فإنه لا يوضع معهم .

كما أن الهالوجينات تتفاعل مع بعضه ليتنتج بين الهالوجينات ومركب ين الهالوجين ثنائى الذرة وله صفات مشابهه للهالوجينات .

كثير من المركبات العضوية مثل البوليمرات والبلاستيك وبعض المركبات العضوية الطبيعية تحتوى على ذرات هالوجين وتعرف هذه المركبات بالمركبات المتحدة مع الهالوجينات . الكلور حتى الآن أكثر الهالوجينات وفرة كما ان الحاجة له كبيرة للغاية ( أيون الكلوريد ) في جسم الإنسان . فمثلا يقوم الكلور يلعب دور أساسي في بعض العمليات التى تتم في المخ حمض جاما-أمينو بيوتيرك، كما يستخدمه الجسم لإنتاج حمض المعدة . كما يستخدم اليود لإنتاج هرمونات الثايرود مثل ثايروكسين . ومن ناحية أخرى لا يعتقد بأن الفلور أو البروم يلعبا دور مهم في جسم الإنسان ، على الرغم من أن كميات ضئيلة من الفلور يمكن أن تقوم بتبييض الأسنان .

ويلاحظ ان الهالوجينات لها إتجاه يمكن رصده عند النزول في المجموعة ، فإنه يلاحظ أن السالبية الكهربية والنشاطية تقل ، أما درجة حرارة الغليان والإنصهار تزيد.

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التاريخ

The fluorine mineral fluorospar was known as early as 1529. Early chemists realized that fluorine compounds contain an undiscovered element, but were unable to isolate it. In 1860, 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. In 1886, Henri Moissan, a chemist in Paris, performed electrolysis on potassium bifluoride dissolved in anhydrous hydrogen fluoride, and successfully isolated fluorine.[1]

Hydrochloric acid was known to alchemists and early chemists. However, elemental chlorine was not produced until 1774, when Carl Wilhelm Scheele heated hydrochloric acid with manganese dioxide. Scheele called the element "dephlogisticated muriatic acid", which is how chlorine was known for 33 years. In 1807, Humphry Davy investigated chlorine and discovered that it is an actual element. Chlorine combined with hydrochloric acid, as well as sulfuric acid in certain 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 human tissue externally and internally, especially the lungs making breathing difficult or impossible depending on the level of contamination.[1]

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 Academy changed the element's name to bromine.[1]

Iodine was discovered by Bernard Courtois, who was using seaweed ash as part of a process for saltpeter manufacture. Courtois typically boiled the seaweed ash with water to generate potassium chloride. However, in 1811, Courtois added sulfuric acid to his process 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 be a new element by Joseph Gay-Lussac.[1]

In 1931, Fred Allison claimed to have discovered element 85 with a magneto-optical machine, and named the element Alabamine, but was mistaken. In 1937, Rajendralal De claimed to have discovered element 85 in minerals, and called the element dakine, but he was also mistaken. An attempt at discovering element 85 in 1939 by Horia Hulubei and Yvette Cauchois via spectroscopy was also unsuccessful, as was an attempt in the same year 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, K.R. Mackenzie, and Emilio G. Segrè, who bombarded bismuth with alpha particles.[1]

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 2022, it is the most recent element to be discovered.


أصل الاسم

In 1811, the German chemist Johann Schweigger proposed that the name "halogen" – 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.[2] Davy's name for the element prevailed.[3] 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.[4][5]

The names of the 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".[1] Tennessine is named after the US state of Tennessee.

السمات

الكيميائية

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.[6]

Halogen bond energies (kJ/mol)[7]
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 reactive, and as 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 high effective nuclear charge. Because the halogens have seven valence electrons in their outermost energy level, they can gain an electron by reacting with atoms of other elements to satisfy the octet rule. Fluorine is the most 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, it can react with glass in the presence of small amounts of water to form silicon tetrafluoride (SiF4). 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 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.

الجزيئات

جزيئات الهالوجينات ثنائية الذرة

The stable halogens form homonuclear diatomic 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.

المركبات

هاليدات الهيدروجين

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.[8]

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.[8]

All halogens form 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 acid, hydroiodic acid, and hydroastatic [ك‍] acid are all strong acids, but hydrofluoric acid is a weak acid.[9]

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.[10] 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.[11] 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.[12] Hydrogen iodide, like other hydrogen halides, is toxic.[13]

هاليدات الفلزات

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[8]

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

2Fe + 3X2 → 2FeX3[8]

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.[8]


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المركبات بين الهالوجينية

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.[14]

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 diatomic halogens. Many interhalogens consist of one or more atoms of fluorine bonding to a heavier halogen. Chlorine can bond with up to 3 fluorine atoms, bromine can bond with up to five fluorine atoms, and iodine can bond with up to seven fluorine atoms. Most interhalogen compounds are covalent gases. However, some interhalogens are liquids, such as BrF3, and many iodine-containing interhalogens are solids.[14]

مركبات الهالوجينات العضوية

Many synthetic organic compounds such as plastic polymers, and a few natural ones, contain halogen atoms; these are known as halogenated compounds or organic halides. Chlorine is by far the most abundant of the halogens in seawater, and the only one needed in relatively large amounts (as chloride ions) by humans. For example, chloride ions play a key role in brain function by mediating the action of the inhibitory transmitter GABA and are also used by 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.[15]

Polyhalogenated compounds

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.

التفاعلات

التفاعلات مع الماء

Fluorine reacts vigorously with water to produce oxygen (O2) and hydrogen fluoride (HF):[16]

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).[17] 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,[18] 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.[19] 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.

الطبيعية والذرية

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.

الهالوجين Standard atomic weight
(u)[n 1][21]
Melting point
(K)
Melting point
(°C)
Boiling point
(K)[22]
Boiling point
(°C)[22]
Density
(g/cm3at 25 °C)
Electronegativity
(Pauling)
First ionization energy
(kJ·mol−1)
Covalent radius
(pm)[23]
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] 171.6 −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 3] 575 302 ? 610 ? 337 ? 6.2–6.5[24] 2.2 ? 887.7 ? 145[25]
Tennessine [294][n 3] ? 623-823[26] ? 350-550[26] ? 883[26] ? 610[26] ? 7.1-7.3[26] - ? 743[27] ? 157[26]
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)[28]
 
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[29]
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

النظائر

Fluorine has one stable and naturally occurring isotope, fluorine-19. 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 14 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.[1]

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 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 have been discovered, with atomic masses ranging from 108 to 145.[1]

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.[1]

Tennessine has only two known synthetic radioisotopes, tennessine-293 and tennessine-294.


. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

التطبيقات

المطهرات

Both chlorine and bromine are used as disinfectants for drinking water, swimming pools, fresh wounds, spas, dishes, and surfaces. They kill bacteria and other potentially harmful microorganisms through a process known as sterilization. Their reactivity is also put to use in bleaching. Sodium hypochlorite, which is produced from chlorine, is the active ingredient of most fabric 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.

الإضاءة

Halogen lamps are a type of incandescent lamp using a tungsten filament in bulbs that have small amounts of a halogen, such as iodine or bromine added. This enables the production of lamps that are much smaller than non-halogen 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 kelvins) 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.[30]

مكونات العقاقير

In drug discovery, the incorporation of halogen atoms into a lead drug candidate results in analogues that are usually more lipophilic and less water-soluble.[31] As a consequence, halogen atoms are used to improve penetration through 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. Aromatic halogen groups are far less reactive than 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.


شاهد أيضا

ملاحظات

  1. ^ The number given in parentheses refers to the measurement uncertainty. This uncertainty applies to the 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.[20]
  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.[21]
  3. ^ أ ب 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.[21]

المراجع

  1. ^ أ ب ت ث ج ح خ د ذ Emsley, John (2011). Nature's Building Blocks. ISBN 978-0199605637.
  2. ^ 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 الألمانية). 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".)
  3. ^ Snelders, H. A. M. (1971). "J. S. C. Schweigger: His Romanticism and His Crystal Electrical Theory of Matter". Isis. 62 (3): 328–338. doi:10.1086/350763. JSTOR 229946. S2CID 170337569.
  4. ^ 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 السويدية). Stockholm, Sweden: P.A. Norstedt & Söner. 6: 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 *).)
  5. ^ 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.
  6. ^ Page 43, Edexcel International GCSE chemistry revision guide, Curtis 2011
  7. ^ Greenwood & Earnshaw 1997, p. 804.
  8. ^ أ ب ت ث ج Jim Clark (2011). "Assorted reactions of the halogens". Retrieved February 27, 2013.
  9. ^ Jim Clark (2002). "THE ACIDITY OF THE HYDROGEN HALIDES". Retrieved February 24, 2013.
  10. ^ "Facts about hydrogen fluoride". 2005. Archived from the original on 2013-02-01. Retrieved 2017-10-28.
  11. ^ "Hydrogen chloride". Retrieved February 24, 2013.
  12. ^ "Hydrogen bromide". Retrieved February 24, 2013.
  13. ^ "Poison Facts:Low Chemicals: Hydrogen Iodid". Retrieved 2015-04-12.
  14. ^ أ ب Saxena, P. B (2007). Chemistry Of Interhalogen Compounds. ISBN 9788183562430. Retrieved February 27, 2013.
  15. ^ Gribble, G. W (2009). Naturally Occurring Organohalogen Compounds - A Comprehensive Update. ISBN 9783211993224. Retrieved April 23, 2022.
  16. ^ "The Oxidising Ability of the Group 7 Elements". Chemguide.co.uk. Retrieved 2011-12-29.
  17. ^ "Solubility of chlorine in water". Resistoflex.com. Retrieved 2011-12-29.
  18. ^ "Properties of bromine". bromaid.org. Archived from the original on December 8, 2007.
  19. ^ "Iodine MSDS". Hazard.com. 1998-04-21. Retrieved 2011-12-29.
  20. ^ "Standard Uncertainty and Relative Standard Uncertainty". CODATA reference. National Institute of Standards and Technology. Retrieved 26 September 2011.
  21. ^ أ ب ت Wieser, Michael E.; Coplen, Tyler B. (2011). "Atomic weights of the elements 2009 (IUPAC Technical Report)" (PDF). Pure Appl. Chem. 83 (2): 359–396. doi:10.1351/PAC-REP-10-09-14. S2CID 95898322. Retrieved 5 December 2012.
  22. ^ أ ب Lide, D. R., ed. (2003). CRC Handbook of Chemistry and Physics (84th ed.). Boca Raton, FL: CRC Press.
  23. ^ Slater, J. C. (1964). "Atomic Radii in Crystals". Journal of Chemical Physics. 41 (10): 3199–3205. Bibcode:1964JChPh..41.3199S. doi:10.1063/1.1725697.
  24. ^ Bonchev, Danail; Kamenska, Verginia (1981). "Predicting the properties of the 113–120 transactinide elements". The Journal of Physical Chemistry. 85 (9): 1177–86. doi:10.1021/j150609a021.
  25. ^ "Get Facts About the Element Astatine". www.thoughtco.com. Retrieved November 12, 2021.
  26. ^ أ ب ت ث ج ح "How Much Do You Know About the Element Tennessine?". www.thoughtco.com. Retrieved November 12, 2021.
  27. ^ "WebElements Periodic Table » Tennessine » properties of free atoms". www.webelements.com. Retrieved November 12, 2021.
  28. ^ Morss, Lester R.; Edelstein, Norman M.; Fuger, Jean (2006). Morss, Lester R; Edelstein, Norman M; Fuger, Jean (eds.). The Chemistry of the Actinide and Transactinide Elements. The Chemistry of the Actinide and Transactinide Elements. Dordrecht, The Netherlands: Springer Science+Business Media. Bibcode:2011tcot.book.....M. doi:10.1007/978-94-007-0211-0. ISBN 978-94-007-0210-3.
  29. ^ "Краткий справочник физико-химических величин Равделя, Л.: Химия, 1974 г. – 200 стр. \\ стр 67 табл. 24" (PDF).
  30. ^ "The Halogen Lamp". Edison Tech Center. Retrieved 2014-09-05.
  31. ^ Thomas, G. (2000). Medicinal Chemistry an Introduction. John Wiley & Sons, West Sussex, UK. ISBN 978-0-470-02597-0.

قالب:Halogens قالب:Fluorides قالب:Chlorides

HI He
LiI BeI2 BI3 CI4 NI3 I2O4, I2O5, I4O9 IF, IF3, IF5, IF7 Ne
NaI MgI2 AlI3 SiI4 PI3, P2I4 S ICl, ICl3 Ar
KI CaI2 Sc TiI4 VI3 Cr MnI2 Fe CoI2 NiI2 CuI ZnI2 Ga2I6 GeI2, GeI4 AsI3 Se IBr Kr
RbI SrI2 Y ZrI4 Nb Mo Tc Ru Rh Pd AgI CdI2 InI3 SnI4, SnI2 SbI3 TeI4 I Xe
CsI BaI2   Hf Ta W Re Os Ir Pt AuI Hg2I2, HgI2 TlI PbI2 Bi Po At Rn
Fr Ra   Rf Db Sg Bh Hs Mt Ds Rg Uub Uut Uuq Uup Uuh Uus Uuo
La Ce Pr Nd Pm SmI2 Eu Gd TbI3 Dy Ho Er Tm Yb Lu
Ac ThI4 Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr