Name: how atoms bond to reach stability
Uploaded: 2023-06-23T15:38:43.000Z
Duration: 1 min 1 s
Channel: JoVE

化学結合は、分子または化合物の原子を一緒に保持します。結合は、原子の価電子殻内の電子が他の原子と供与または共有されるときに形成されます。
例えば、イオン結合は、原子が電子を供与または受け入れ、原子価殻を満たすときに形成されます。電子を供与して正に帯電する原子を陽イオン、電子を受け入れて負に帯電する原子を陰イオンと呼びます。
食卓塩では、ナトリウムカチオンと塩化物アニオンとの間の会合はイオン結合です。
共有結合は、1つ以上の価電子ペアを相互に共有する原子間に形成されます。
たとえば、2つの水素原子は一対の電子を共有し、単一の共有結合を形成することができます。酸素と窒素は2つまたは3つの電子対を共有し、二重結合と三重結合を形成することができます。

化学結合の紹介

Introduction to Chemical Bonds

化学結合 外部の最もエネルギー準位にある電子は、原子のエネルギー的安定性と他の原子との化学結合の傾向を決定します。内部の電子殻は最大2つの電子を持つことができますが、次の2つの電子殻はそれぞれ最大8つの電子を持つことができます。これはオクテット則として知られており、これにより、内部の殻を除いて、原子は最もエネルギー的に安定しているときに最外殻に8つの電子を持つとされます。 しかし、すべての元素が最外殻を埋めるのに十分な電子を持っているわけではないため、原子は他の原子と化学結合を形成し、安定な電子配置を得るために必要な電子を得ます。したがって、化学結合とは、分子や化合物内で原子を結びつける力です。 イオン結合 原子は最外殻を埋めるために電子を得たり失ったりすることができます。そうすることで、電気的に帯電し、イオンと呼ばれるようになります。陽イオンは電子を失った陽性に帯電した原子であり、電子を得て帯電した陰イオンは陰性に帯電します。陽イオンと陰イオンの逆の電荷によって、イオン結合を形成するための中間程度の強い相互引力が働き、原子は近接しています。イオン結合は、イオン結合によって存在する普通の食塩のことを指します。 共有結合 オクテット則が満たされる別の方法は、原子間で電子を共有して共有結合を形成することです。この結合は、生物分子の中でイオン結合よりも強力であり、より一般的です。共有結合は、DNAやタンパク質などの炭素ベースの有機分子によく見られます。共有結合は、水、二酸化炭素、酸素などの無機分子でも見られます。 水素結合 水素結合は、既に1つの電気陰性原子（たとえば、水分子中の酸素）に結びついている弱陽性の水素原子が、別の分子の他の電気陰性原子に引かれることで形成されます。自然界で最も一般的な水素結合の例は、水分子の分子間で発生します。2つの雨滴が大きな水滴になるときや川が合流するときに起こります。水素結合は、水分子の弱陰性の酸素原子が他の2つの水分子の弱陽性な水素原子に引かれるために起こります。

このテキストは、<a href="https://openstax.org/books/anatomy-and-physiology-2e/pages/2-2-chemical-bonds?query=chemical%20bond&target=%7B%22type%22%3A%22search%22%2C%22index%22%3A0%7D#fs-id1493624">Openstax, Anatomy and Physiology 2e, Section 2.2: Chemical Bonds.</a> <a href="https://openstax.org/books/biology-ap-courses/pages/2-1-atoms-isotopes-ions-and-molecules-the-building-blocks?query=chemical%20bonds">Openstax,</a> <a href="https://openstax.org/books/biology-ap-courses/pages/2-1-atoms-isotopes-ions-and-molecules-the-building-blocks?query=chemical%20bonds">Biology for AP® Courses</a> <a href="https://openstax.org/books/biology-ap-courses/pages/2-1-atoms-isotopes-ions-and-molecules-the-building-blocks?query=chemical%20bonds">Section</a> <a href="https://openstax.org/books/biology-ap-courses/pages/2-1-atoms-isotopes-ions-and-molecules-the-building-blocks?query=chemical%20bonds">2.1 Atoms, Isotopes, Ions, and Molecules: The Building Blocks.</a>

化学結合
最も外側のエネルギー準位の電子は、原子のエネルギー安定性と化学結合を形成する傾向を決定します...

Education

JoVE Core

Anatomy and Physiology

解剖生理学

Unit 1

ユニット1

Fundamentals of Chemistry

化学の基礎

KEY TERMS AND CONCEPTS

主要用語と概念

how atoms bond to reach stability

Atoms bond to become more stable, and their outermost electrons play the biggest role in that process. The inner electron shell can hold two electrons. The next two shells can each hold eight electrons. This is called the octet rule. It states that, except for the innermost shell, atoms are most stable when their valence shell, or outer shell, has eight electrons.

When atoms do not have enough electrons to fill that outer shell, they form chemical bonds with other atoms. A chemical bond is the force that holds atoms together in a molecule or compound. These bonds let atoms reach a more stable electron arrangement.

One common type is an ionic bond. In this case, atoms gain or lose electrons to fill their valence shell. When they do this, they become ions. A cation is a positively charged ion that has lost electrons. An anion is a negatively charged ion that has gained electrons. The opposite charges attract each other and keep the ions close together. This close association forms an ionic bond. Table salt is a common example of a substance made through ionic bonding.

Another way atoms satisfy the octet rule is by sharing electrons. This creates covalent bonds. Covalent bonds are stronger and much more common than ionic bonds in the molecules of living organisms. They are found in carbon-based organic molecules such as DNA and proteins. They also occur in inorganic molecules like water, carbon dioxide, and oxygen.

Hydrogen bonds are a weaker kind of attraction. They form when a weakly positive hydrogen atom, already bonded to another electronegative atom such as oxygen, is attracted to a different electronegative atom in another molecule. Water is the most common example. Hydrogen bonding helps explain why raindrops can merge into larger beads and why a creek can flow into a river.

How Atoms Bond to Reach Stability

what is matter?

Matter, Mass, and Weight Basics

Matter is the substance that makes up the universe, from a grain of sand to a star. Scientists define matter as anything that occupies space and has mass. Mass is the amount of matter in an object, while weight depends on gravity. Mass stays the same whether an object is on Earth or in the zero-gravity environment of outer space. Weight changes when gravity changes. An object weighs more where gravity is stronger and less where gravity is weaker. A piece of cheese that weighs a pound on Earth...

the periodic table and organismal elements

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Organismal Elements in the Periodic Table

The periodic table helps identify the elements that make up living organisms. Biology groups these as organismal elements because they are the chemical building blocks of life. These elements are found in different amounts in the body. Some are present in large quantities, while others are needed only in small amounts. The video connects the periodic table to the elements that organisms actually use. Understanding organismal elements helps students link chemistry to biology. It shows how...

atomic structure

From Atomos to the Modern Atom

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chemical symbols

Chemical Symbols and Element Names

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atomic number and mass number

Atomic Identity, Mass, and Isotopes

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atomic weight

Atomic Mass and Mole Calculations

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isotopes and radioisotopes

Radioisotopes in Medicine and Imaging

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electron behavior

Electron Shells and Discovery

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introduction to chemical bonds

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ionic bonds

Ionic Bonds and Charge Transfer

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covalent bonds

Polar and Nonpolar Covalent Bonds

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hydrogen bonds

Hydrogen Bonding and DNA Stability

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ions, molecules, and compounds

Atomic Charges, Bonds, and Compounds

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states of matter

Solids, Liquids, Gases, and Plasma

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colloids and suspensions

Suspensions, Sedimentation, and Colloids

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Chemical Reaction Basics and Equilibrium

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Anabolism, Catabolism, and ATP Use

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types of chemical reactions: exchange and reversible

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Electron Transfer and Chemical Equilibrium

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Chemical Energy and Reaction Types

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factors influencing the rate of chemical reactions

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Chemical Reaction Rates and Catalysts

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acids, bases and neutralization reactions

How pH Affects Cells and Digestion

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key terms and concepts

Learn how atoms use ionic, covalent, and hydrogen bonds to reach stability. Explore valence electrons, ions, and examples like salt and water.

How Atoms Bond to Reach Stability | JoVE K12

anatomy and physiology

JoVE Core 解剖学と生理学では、人体の解剖学的および生理学的な詳細を、包括的で明確で魅力的なビデオ アニメーションで紹介します。このレッスン集は、人体の構造、コンポーネント、機能、要件に焦点を当てています。この知識を実際の医療および研究現場で応用することを実証する科学者による実際のビデオによって補完されています。

How Atoms Bond to Reach Stability

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