Name: halogens: trends and reactions
Uploaded: 2020-09-03T13:38:28.000Z
Duration: 3 min 1 s
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K12 Standards

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NC K-12 Science Standard Course of Study

9-12

Physical Science

Matter and its Interactions

PS.PSc.1.6

Halogens

ハロゲンは フッ素 塩素 臭素 ヨウ素 アスタチンの 5つの非金属元素からなる グループで 第17族に属します 元素ハロゲンは二原子分子として 存在します 室温では フッ素と塩素は気体 臭素は液体 ヨウ素は固体です 第5元素のアスタチンは 希少で放射性の高い固体で その性質は あまり知られていません ハロゲンの物理的性質は 元素の色など 族が下がるにつれて 変化します 原子番号が増えるほど 原子半径が大きくなり 融点や沸点は フッ素からヨウ素に向かって 上昇傾向にあります 一方 電子陰性度 反応性 電子親和性などの 周期的性質は 原子番号が 下がるにつれて減少します ハロゲンの電子配置は 7つの価電子を持ち 最も近い希ガス配置に 到達するには電子が1つ 足りないことを示しています そのため ハロゲンは 高い電子陰性度を示し オクテットを完成させるために 電子を1個増やす傾向が強く 他の基に比べて反応性が高く 強力な酸化剤となっています ハロゲンの中ではフッ素が 最も強力な酸化剤であり ヨウ素は最も弱い酸化剤です また ハロゲンは 中性原子が 電子を得たときの エネルギーの変化である 負の電子親和性が 高いことも特徴です これは中性原子が電子を 獲得したときのエネルギー変化で 負の値は反応の発熱性を示し キロジュール/モルで 表されます ハロゲンは多くの金属と反応し 金属ハロゲン化物を生成します 例えば塩素とナトリウムは反応し 塩化ナトリウムを生成しますが これはイオン性化合物です ハロゲンは水素と反応して ハロゲン化水素と呼ばれる 極性の共有結合化合物を 形成します また ハロゲンは水と反応します 水とフッ素の反応は 非常に発熱性であり 強酸のフッ化水素と 酸素を生成します 一方 塩素は反応が遅く 強酸である塩酸と次亜塩素酸を 生成します また ハロゲンは互いに反応して ハロゲン間化合物と呼ばれる 二価の共有結合の化合物を 生成することができます 例えば 臭素はフッ素と 反応することで 三フッ化臭素を生成します

ハロゲン

17 族の元素はハロゲンと呼ばれ、非金属です。 室温では、フッ素と塩素は気体、臭素は液体、ヨウ素は固体です。 アスタチンは非常に不安定な放射性元素であるため、現在、その特性のほとんどは半減期が短いため不明です。 テネシンはまたこの族にあると予測されている合成元素です。
 
 ハロゲンは単原子ではなく、二原子分子として存在します。原子半径はフッ素からヨウ素に向かって大きくなります。ハロゲンの原子価殻の電子配置はns2np5で、電子を受け入れて希ガス配置になる性質があります。 ハロゲンのさまざまな性質を表1に示します。 
 
 表 1: ハロゲンの特性 
 
 <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;">元素 </td>
 <td style="color: black; border: 1px solid black; text-align: center;">電子の特性 </td>
 <td style="color: black; border: 1px solid black; text-align: center;">原子半径（ 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;">25 ° C での密度 </td>
 <td style="color: black; border: 1px solid black; text-align: center;">融点（ ° 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>
 
 ハロゲンの電子親和力は負の値が大きいので、強力な酸化剤となります。フッ素は、電子親和力が最も負の値を持つグループの中で最も強力な酸化剤です。ハロゲンは金属と反応して電子を獲得し、対応する金属ハロゲン化物を生成します。例えば、塩素は鉄と反応して塩化鉄を、ナトリウムと反応して塩化ナトリウムを生成します。ハロゲンは水素と反応してハロゲン化水素を生成し、これが水に溶解してハロゲン化水素酸を生成します。フッ化水素酸は最も弱いハロゲン酸です。フッ素は水と活発に反応します。この反応は高い発熱性をもち、酸素を生成します。塩素は水との反応はそれほど活発ではありません。この反応で生成される次亜塩素酸は強力な酸化剤です。 
 
 ハロゲンは互いに反応してハロゲン間化合物を形成しますが、その多くは二元化合物です。ハロゲン間化合物の一般的な分子式はABnであり、Aは原子番号の大きいハロゲンで、奇数です。ハロゲン間化合物の例としては、ICl，IBr，BrF，BrCl，ClFなどがあります。ハロゲンは炭素と反応して商業的に重要な化合物を形成します。 
 
 このテキストは <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 から引用したものです。</a>

ハロゲンとして知られるグループ17の元素は非金属です。室温では、フッ素と塩素は気体、臭素は液体、ヨウ素は固体です。...

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Chemistry

化学

Periodic Properties of the Elements

元素の周期的な性質

KEY TERMS AND CONCEPTS

主要用語と概念

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

periodic classification of the elements

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atomic radii and effective nuclear charge

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Periodic Trends in Atomic Size

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ionic radii

How Ionic Charge Changes Ion Size

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electron affinity

Electron Affinity Trends on the Periodic Table

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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...

noble gases

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key terms and concepts

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

Halogens: Trends and Reactions | JoVE K12

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Pennsylvania State Academic Standards

Chemical Reactions

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Structure and Properties of Matter

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High School

Matter And Its Interactions

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Study Of Matter

Periodic trends of the elements

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Matter and Its Interactions

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Motion and Stability: Forces and Interactions

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Georgia Standards of Excellence

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Vapor Pressure

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Phase Transitions: Melting and Freezing

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Phase Transitions: Sublimation and Deposition

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Heating and Cooling Curves

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PS.PSc.1.2

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Physical and Chemical Properties of Matter

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Physical Properties of Matter

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Intermolecular vs Intramolecular Forces

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Intermolecular Forces

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

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PS.PSc.1.3

The Atomic Theory of Matter

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Subatomic Particles

Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller ...

The Bohr Model

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Emission Spectra

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The Uncertainty Principle

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Use models to interpret the data presented in Bohr diagrams and electron dot diagrams for neutral atoms of elements 1 through 18.

PS.PSc.1.4

Ions and Ionic Charges

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PS.PSc.1.5

The Periodic Table

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Periodic Classification of the Elements

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Atomic Radii and Effective Nuclear Charge

The elements in groups of the periodic table exhibit similar chemical behavior. This similarity occurs because the members of a group have the same number ...

Ionic Radii

Ionic radius is the measure used to describe the size of an ion. A cation always has fewer electrons and the same number of protons as the parent atom; it ...

Ionization Energy

The amount of energy required to remove the most loosely bound electron from a gaseous atom in its ground state is called its first ionization energy ...

Electron Affinity

The electron affinity (EA) is the energy change for adding an electron to a gaseous atom to form an anion (negative ion).



This process can be either ...

Alkali Metals

Group 1 elements are soft and shiny metallic solids. They are malleable, ductile, and good conductors of heat and electricity. The melting points of the ...

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


The elements in group 18 are noble gases (helium, neon, argon, krypton, xenon, and radon). They earned the name &ldquo;noble&rdquo; because they were ...

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

Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence ...

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.

PS.PSc.2.1

Nomenclature of Alkanes

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Use models to apply International Union of Pure and Applied Chemistry (IUPAC) conventions to name and write formulas for simple compounds.

PS.PSc.2.2

Understand types, properties, and structure of matter.

Halogens: Trends and Reactions

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