Name: atomic charges, bonds, and compounds
Uploaded: 2023-06-23T15:38:43.000Z
Duration: 1 min 23 s
Channel: JoVE

Ionen sind elektrisch geladene Atome, die Elektronen gewonnen oder verloren haben. Ein Atom, das Elektronen verliert und positiv geladen wird, ist ein Kationen, während ein Atom, das Elektronen gewinnt und negativ geladen wird, ein Anion ist.
Ionen sind für viele physiologische Prozesse unerlässlich, wie z. B. die Übertragung von Nervenimpulsen und die Muskelkontraktion.
Moleküle sind Kombinationen aus zwei oder mehr Atomen, die sich Elektronen teilen. Sie können aus Atomen eines Elements bestehen, wie einem Sauerstoffmolekül, oder aus Atomen verschiedener Elemente, wie einem Wassermolekül.
Eine Verbindung ist eine Kombination von Atomen verschiedener Elemente, die chemisch in einem festen Verhältnis gebunden sind, unabhängig davon, ob Elektronen übertragen oder geteilt werden.
Ionische Verbindungen entstehen durch elektrostatische Wechselwirkung zwischen metallischen und nichtmetallischen Ionen, wie in gewöhnlichem Speisesalz, wobei ein Natriumkation und ein Chloridanion durch elektrostatische Wechselwirkungen miteinander verbunden sind.
Molekulare Verbindungen entstehen, wenn nichtmetallische Atome über kovalente Bindungen gebunden werden. Zum Beispiel ist Methan eine molekulare Verbindung, bei der sich vier Wasserstoffatome Elektronen mit einem Kohlenstoffatom in einem bestimmten Verhältnis teilen.

ionen, moleküle und verbindungen

Ionen - Wenn ein Atom an einer chemischen Reaktion teilnimmt, die zur Abgabe oder Aufnahme eines oder mehrerer Elektronen führt, wird das Atom positiv oder negativ geladen. Dies passiert häufig bei den meisten Atomen, um eine vollständige Valenzschale zu haben. Dies kann entweder dadurch geschehen, dass Elektronen aufgenommen werden, um eine Schale zu füllen, die mehr als zur Hälfte gefüllt ist oder indem Elektronen abgegeben werden, um eine Schale zu leeren, die weniger als zur Hälfte gefüllt ist, wodurch die nächst kleinere Elektronenschale als neue, volle Valenzschale zurückbleibt. Ein Atom mit einer elektrischen Ladung - positiv oder negativ - ist ein Ion. Kalium (K) ist zum Beispiel ein wichtiges Element in allen Körperzellen. Seine Ordnungszahl beträgt 19. Es hat nur ein Elektron in seiner Valenzschale. Aufgrund dieser Eigenschaft ist es sehr wahrscheinlich, dass Kalium an chemischen Reaktionen teilnimmt, bei denen es ein Elektron abgibt. Durch den Verlust wird die positive Ladung der Protonen von Kalium einflussreicher sein, als die negative Ladung der Elektronen von Kalium. Mit anderen Worten, das resultierende Kaliumion wird leicht positiv sein. Ein positiv geladenes Ion nennt man Kation. Ein weiteres Element, Fluor (F), ein Bestandteil von Knochen und Zähnen, hat die Ordnungszahl 9. Es hat sieben Elektronen in seiner Valenzschale. Es ist sehr wahrscheinlich, dass Fluor sich mit anderen Atomen so verbindet, dass es ein Elektron aufnimmt. Wenn dies der Fall ist, sind seine Elektronen um eins zahlreicher als seine Protonen und es wird insgesamt eine negative Ladung haben. Ein negativ geladenes Ion nennt man Anion. Ionen sind für die normale Körperfunktion wichtig, daher können Ungleichgewichte zu Gesundheitsproblemen führen. Zum Beispiel kann ein Natriumion-Ungleichgewicht kardiovaskuläre Erkrankungen verursachen. Niedrige Calciumwerte im Blut können Tetanie verursachen - unkontrollierte unwillkürliche Muskelkontraktionen. Moleküle - Moleküle sind einfach zwei oder mehr Atome, die chemisch miteinander verbunden sind. Moleküle können aus Atomen desselben Elements bestehen, wie ein Sauerstoffgasmolekül, das durch die Bindung zwischen zwei Sauerstoffatomen entsteht. Moleküle können aber auch durch Bindung zwischen Atomen unterschiedlicher Elemente entstehen, wie ein Kohlendioxidgasmolekül, das zwischen Sauerstoff- und Kohlenstoffatomen gebildet wird. Verbindungen - Eine Verbindung ist eine reine Substanz, die durch Bindung von zwei oder mehr Atomen in einem festen Verhältnis gebildet wird. Beispielsweise ist die Verbindung Glukose ein wichtiger Brennstoff für den Körper. Es besteht immer aus den gleichen drei Elementen: Kohlenstoff, Wasserstoff und Sauerstoff, in den gleichen relativen Mengen. In Glukose kommen auf zwölf Wasserstoffeinheiten immer sechs Kohlenstoff- und sechs Sauerstoffeinheiten. Dieser Text wurde teilweise angepasst von <a href="https://openstax.org/books/anatomy-and-physiology-2e/pages/2-2-chemical-bonds?query=when%20a%20atom%20participates&target=%7B%22type%22%3A%22search%22%2C%22index%22%3A0%7D#fs-id2113058">Openstax, Anatomy and Physiology 2e, Section 2.2 Chemical Bonds</a> and Openstax, <a href="https://openstax.org/books/anatomy-and-physiology-2e/pages/2-1-elements-and-atoms-the-building-blocks-of-matter?query=For%20example%2C%20the%20compound%20glucose%20is%20an%20important%20body%20fuel.%20It%20is%20always%20composed%20of%20the%20same%20three%20elements&target=%7B%22type%22%3A%22search%22%2C%22index%22%3A0%7D#fs-id1882474">Anatomy and Physiology 2e, Section 2.1 Elements and Atoms: The Building Blocks of Matter</a>.

Ionen, Moleküle und Verbindungen

Ionen - Wenn ein Atom an einer chemischen Reaktion teilnimmt, die zur Abgabe oder Aufnahme eines oder mehrerer Elektronen führt, wird das Atom positiv ...

Education

Lehre

JoVE Core

Anatomy and Physiology

Anatomie und Physiologie

Unit 1

Einheit 1

Fundamentals of Chemistry

Grundlagen der Chemie

KEY TERMS AND CONCEPTS

KERNBEGRIFFE UND KONZEPTE

Ions, Molecules, and Compounds

atomic charges, bonds, and compounds

Atoms can gain or lose electrons during chemical reactions and become ions. An ion is an atom with an electrical charge. This charge is positive or negative, and it often helps the atom reach a full valence shell.

Some atoms are more likely to donate electrons, while others are more likely to accept them. Potassium is one example. It has atomic number 19 and one electron in its valence shell, so it is likely to donate that electron and become a slightly positive ion called a cation. Fluorine is another example. It has atomic number 9 and seven electrons in its valence shell, so it is likely to accept one electron and become a negatively charged ion called an anion.

Ions are important for normal body function, so an imbalance can cause health problems. A sodium ion imbalance can contribute to cardiovascular diseases. Low blood calcium levels can also cause tetany, which is marked by uncontrollable involuntary muscle contractions.

Molecules and compounds are related but not the same. A molecule is two or more atoms chemically bonded together. The atoms may be the same element, as in oxygen gas, or different elements, as in carbon dioxide gas. A compound is a pure substance made when two or more atoms bond in a fixed proportion.

Glucose is a useful example of a compound. It is an important body fuel and always contains the same elements in the same relative amounts: carbon, hydrogen, and oxygen. In glucose, there are always six carbon units and six oxygen units for every twelve hydrogen units.

Atomic Charges, Bonds, and Compounds

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the periodic table and organismal elements

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chemical symbols

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atomic weight

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Atomic mass and mole calculations help explain how much matter is in atoms and compounds. Protons and neutrons have about the same mass, about 1.67 × 10 -24 grams. Scientists define that mass as one atomic mass unit, or amu, also called one Dalton. Electrons are much lighter than protons. They weigh only 9.11 × 10 -28 grams, or about 1/1800 of an atomic mass unit. Because of that small mass, electrons do not add much to an element’s overall atomic mass. When chemists calculate atomic mass,...

isotopes and radioisotopes

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electron behavior

Electron Shells and Discovery

Electrons are negatively charged subatomic particles that stay near the positively charged nucleus of an atom. They occupy spaces linked to energy levels called shells. They are also arranged into subshells and orbitals within each shell. An electron’s shell shows its general energy level. Electrons closer to the nucleus have less energy, while electrons farther away have more energy. The outer shells have more space, so they can hold more electrons than the inner shells. Subshells describe...

introduction to chemical bonds

How Atoms Bond to Reach Stability

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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

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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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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

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Acids, bases, and pH help control how cells and body systems work. In biology, pH can strongly affect enzymes, proteins, and nucleic acids. Enzymes work best within a certain pH range, and pH changes can alter their structure or denature them, which changes how they function. Acids release hydrogen ions, or H+, in solution. A hydrogen ion is a proton, so it is very reactive in chemical reactions. Strong acids release all of their H+ in water and ionize completely. Hydrochloric acid (HCl) is a...

key terms and concepts

Learn how atoms become ions, why cations and anions form, and how molecules and compounds differ using potassium, fluorine, oxygen, carbon dioxide, and glucose.

Atomic Charges, Bonds, and Compounds | JoVE K12

anatomy and physiology

JoVE Core Anatomy and Physiology showcases the anatomical and physiological details of the human body in comprehensive, clear, and engaging video animations. This collection of lessons focuses on the structures, components, functions, and requirements of the human body. It is complemented by scientist-in-action videos that demonstrate the application of this knowledge in real-world medical and research settings.

Atomic Charges, Bonds, and Compounds

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