Name: halogens: trends and reactions
Uploaded: 2020-09-03T13:38:28.000Z
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Halogens

Halogene sind eine Gruppe von fünf nichtmetallischen Elementen Fluor, Chlor, Brom, Jod und Astat die zur Gruppe 17 gehören. Elementare Halogene existieren als zweiatomige Moleküle. Bei Raumtemperatur sind Fluor und Chlor Gase, Brom ist eine Flüssigkeit, und Jod ist ein Feststoff.Über die Eigenschaften des fünften Elements, Astat, ist weniger bekannt. Das ist ein seltener und hoch radioaktiver Feststoff. Die physikalischen Eigenschaften von Halogenen, wie z.B.Elementfarbe, nehmen in der Gruppe ab Die Atomradien nehmen mit zunehmender Ordnungszahl zu. Genauso nehmen die Schmelz-und den Siedepunkt von Fluor zu Jod zu. Im Gegensatz dazu, nehmen die periodischen Eigenschaften wie Elektronegativität, Reaktivität und Elektronenaffinität in der Gruppe ab.Elektronenkonfigurationen von Halogenen gibt an, dass sie sieben Valenzelektronen haben und damit ein Elektron zu wenig, um ihre nächste Edelgas-Konfiguration zu erreichen. Daher weisen Halogene eine hohe Elektronegativitäten auf, mit einer starken Tendenz, um ein zusätzliches Elektron zu gewinnen um ihr Oktett zu vervollständigen, wodurch sie hochreaktive und leistungsfähige Oxidationsmittel werden, im Vergleich zu anderen Gruppen. Fluor ist unter den Halogenen das stärkste Oxidationsmittel und Jod am schwächsten.Auch Halogene weisen starke negative Elektronenaffinitäten auf. Das ist die Änderung der Energie, wenn ein Elektron von einem neutralem Atom aufgenommen wird. Das wird in kJ/mol angegeben, und der negative Wert stellt die exotherme Natur der Reaktion dar.Halogene reagieren mit den meisten Metallen unter Bildung von Metallhalogeniden. Zum Beispiel reagieren Chlor und Natrium zur Herstellung von Natriumchlorid, bei dem es sich um eine ionische Verbindung handelt. Halogene reagieren mit Wasserstoff zu polaren kovalenten Verbindungen, die Halogenwasserstoffe, welche sich oft in Wasser lösen, und zur Bildung von Halogenwasserstoffsäuren führen.Halogene reagieren auch mit Wasser. Die Reaktion von Fluor mit Wasser ist stark exotherm, unter der Bildung von Fluorwasserstoff einer starken Säure und Sauerstoff. Chlor reagiert jedoch langsamer, mit der Herstellung von Salzsäure und hypochloriger Säure die ein starkes Oxidationsmittel ist.Außerdem können Halogene miteinander reagieren um binäre, kovalente Verbindungen zu erzeugen, die als Interhalogenverbindungen bezeichnet werden. Zum Beispiel reagiert Brom mit Fluor unter Bildung von Bromtrifluorid.

halogene

Elemente der Gruppe 17, sogenannte Halogene, sind Nichtmetalle. Bei Raumtemperatur sind Fluor und Chlor Gase, Brom ist eine Flüssigkeit und Jod ist ein Feststoff. Astat ist ein äußerst instabiles radioaktives Element, daher sind die meisten seiner Eigenschaften aufgrund seiner kurzen Halbwertszeit derzeit unbekannt. Tennessin ist ein synthetisches Element, von dem vorhergesagt wird, dass es ebenfalls zu dieser Gruppe gehört. Die Halogene liegen normalerweise nicht als einzelne Atome vor, sondern als zweiatomige Moleküle. Der Atomradius vergrößert sich von Fluor zu Jod. Die Elektronenkonfiguration der Valenzschale von Halogenen ist ns2np5 und sie neigen dazu, ein Elektron aufzunehmen um die Edelgaskonfiguration zu erreichen. Die verschiedenen Eigenschaften von Halogenen sind in Tabelle 1 aufgeführt. Tabelle 1: Eigenschaften der Halogene. <table style="margin-left: auto; margin-right: auto;"> <tbody style="border: 1px solid black;"> <tr> <td style="color: black; border: 1px solid black; text-align: center;">Element</td> <td style="color: black; border: 1px solid black; text-align: center;">Elektronenkonfiguration</td> <td style="color: black; border: 1px solid black; text-align: center;">Atomradius (pm)</td> <td style="color: black; border: 1px solid black; text-align: center;">IE1 (kJ/mol)</td> <td style="color: black; border: 1px solid black; text-align: center;">EA (kJ/mol)</td> <td style="color: black; border: 1px solid black; text-align: center;">Dichte bei 25 °C </td> <td style="color: black; border: 1px solid black; text-align: center;">Schmelzpunkt (°C)</td> </tr> <tr> <td style="color: black; border: 1px solid black; text-align: center;">F</td> <td style="color: black; border: 1px solid black; text-align: center;">[He] 2s22p5</td> <td style="color: black; border: 1px solid black; text-align: center;">71</td> <td style="color: black; border: 1px solid black; text-align: center;">1680</td> <td style="color: black; border: 1px solid black; text-align: center;">-328</td> <td style="color: black; border: 1px solid black; text-align: center;">1.70 g/L</td> <td style="color: black; border: 1px solid black; text-align: center;">-219</td> </tr> <tr> <td style="color: black; border: 1px solid black; text-align: center;">Cl</td> <td style="color: black; border: 1px solid black; text-align: center;">[Ne] 3s23p5</td> <td style="color: black; border: 1px solid black; text-align: center;">99</td> <td style="color: black; border: 1px solid black; text-align: center;">1250</td> <td style="color: black; border: 1px solid black; text-align: center;">-348</td> <td style="color: black; border: 1px solid black; text-align: center;">3.12 g/L</td> <td style="color: black; border: 1px solid black; text-align: center;">-101</td> </tr> <tr> <td style="color: black; border: 1px solid black; text-align: center;">Br</td> <td style="color: black; border: 1px solid black; text-align: center;">[Ar] 4s24p5</td> <td style="color: black; border: 1px solid black; text-align: center;">114</td> <td style="color: black; border: 1px solid black; text-align: center;">1140</td> <td style="color: black; border: 1px solid black; text-align: center;">-324</td> <td style="color: black; border: 1px solid black; text-align: center;">3.19 g/cm3</td> <td style="color: black; border: 1px solid black; text-align: center;">-7</td> </tr> <tr> <td style="color: black; border: 1px solid black; text-align: center;">I</td> <td style="color: black; border: 1px solid black; text-align: center;">[Kr] 5s25p5</td> <td style="color: black; border: 1px solid black; text-align: center;">133</td> <td style="color: black; border: 1px solid black; text-align: center;">1010</td> <td style="color: black; border: 1px solid black; text-align: center;">-295</td> <td style="color: black; border: 1px solid black; text-align: center;">3.96 g/cm3</td> <td style="color: black; border: 1px solid black; text-align: center;">114</td> </tr> </tbody> </table> Die Elektronenaffinitäten von Halogenen haben stark negative Werte; Daher sind die Halogene starke Oxidationsmittel. Fluor ist das stärkste Oxidationsmittel der Gruppe mit der negativsten Elektronenaffinität. Die Halogene reagieren mit Metallen, nehmen das Elektron auf und es entsteht das entsprechende Metallhalogenid. Beispielsweise reagiert Chlor mit Eisen zu Eisenchlorid und mit Natrium zu Natriumchlorid. Die Halogene reagieren mit Wasserstoff zu Halogenwasserstoffen, welche sich gut in Wasser lösen und Halogenwasserstoffsäuren bilden. Flusssäure ist die schwächste Halogensäure. Fluor reagiert heftig mit Wasser. Die Reaktion ist stark exotherm und erzeugt Sauerstoff. Die Reaktion von Chlor mit Wasser ist weniger heftig. Die bei dieser Reaktion entstehende hypochlorige Säure ist ein starkes Oxidationsmittel. Halogene können auch miteinander reagieren und Interhalogenverbindungen bilden, von denen viele binäre Verbindungen sind. Die allgemeine Summenformel für Interhalogenverbindungen lautet ABn, wobei A das Halogen mit der höheren Ordnungszahl und n eine ungerade Zahl ist. Einige Beispiele für Interhalogenverbindungen sind ICl, IBr, BrF, BrCl, ClF. Die Halogene reagieren mit Kohlenstoff zu kommerziell wichtigen Verbindungen. Beispielsweise reagiert Ethylen mit Fluor zu Perfluorethylen. Dieser Text wurde adaptiert von<a href="https://openstax.org/books/chemistry-2e/pages/6-5-periodic-variations-in-element-properties">Openstax, Chemistry 2e, Section 6.5: Periodic Variations in Element Properties.</a>

Halogene

Elemente der Gruppe 17, die als Halogene bekannt sind, sind Nichtmetalle. Bei Raumtemperatur sind Fluor und Chlor Gase, Brom eine Flüssigkeit und Jod ein Feststoff. ...

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halogens: trends and reactions

Halogens are Group 17 nonmetals that show clear trends in structure and reactivity. At room temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid. Astatine is highly unstable and radioactive, so most of its properties are still unknown because it has a very short half-life. Tennessine is a synthetic element that is also predicted to belong to this group.

These elements do not usually exist as single atoms. Instead, they form diatomic molecules, which means each molecule has two atoms. Their atomic radius increases from fluorine to iodine, and their outer-shell electron pattern is ns2 np5. This electron arrangement helps explain why halogens tend to gain one electron and reach a noble gas configuration.

The table of halogen properties shows important changes across the group. Fluorine has the smallest atomic radius, while iodine has the largest. First ionization energy decreases from fluorine to iodine, and electron affinity stays strongly negative for the group. Because of this, halogens are powerful oxidizing agents, and fluorine is the strongest oxidizing agent in the group.

Halogens react with metals to form metal halides. For example, chlorine reacts with iron to make iron chloride, and it reacts with sodium to make sodium chloride. They also react with hydrogen to form hydrogen halides. When these dissolve in water, they produce hydrohalic acids, and hydrofluoric acid is the weakest haloacid.

Halogens also react with water, but not in the same way. Fluorine reacts very vigorously, and the reaction is highly exothermic, which means it releases a large amount of heat. It also produces oxygen. Chlorine reacts less vigorously with water, and the hypochlorous acid formed is a strong oxidizing agent.

Halogens can react with one another to form interhalogen compounds, which are often binary compounds. Their general formula is ABn, where A is the halogen with the higher atomic number and n is an odd number. Examples include ICl, IBr, BrF, BrCl, and ClF. Halogens also react with carbon to form useful compounds, such as perfluoroethylene from the reaction of ethylene with fluorine.

Halogens: Trends and Reactions

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halogens

Halogens are Group 17 nonmetals that show clear trends in structure and reactivity. At room temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine is a solid. Astatine is highly unstable and radioactive, so most of its properties are still unknown because it has a very short half-life. Tennessine is a synthetic element that is also predicted to belong to this group. These elements do not usually exist as single atoms. Instead, they form diatomic molecules, which means...

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Explore halogen trends, from physical states and electron configuration to oxidizing strength, metal halides, hydrohalic acids, and interhalogen compounds.

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Phase Diagrams

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Physical and Chemical Properties of Matter

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Physical Properties of Matter

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Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility

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The Atomic Theory of Matter

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The Uncertainty Principle

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The Periodic Table

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Periodic Classification of the Elements

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Ionic Radii

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Electron Affinity

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This process can be either ...

Alkali Metals

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Group 17 elements, known as halogens, are nonmetals. At room temperature, fluorine and chlorine are gases, bromine is a liquid, and iodine a solid. ...

Noble Gases


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Use the Periodic Table as a model to predict the relative properties (metallic/nonmetallic character, ionic charge, and reactivity) and arrangement of elements based on the pattern of valence electrons in the outermost energy levels of atoms.

Types of Chemical Bonds

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Ionic Bonding and Electron Transfer

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Covalent Bonding and Lewis Structures

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Bonding in Metals

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Construct an explanation to classify the type of chemical bond that occurs (covalent, ionic, or metallic) in a given substance.

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Understand types, properties, and structure of matter.

Halogens: Trends and Reactions

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