Name: matter: elements, compounds, and mixtures
Uploaded: 2020-09-03T13:38:25.000Z
Duration: 3 min 35 s
Channel: JoVE

K12 Standards

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North Carolina K-12 Science Standard Course of Study

9-12

Chemistry

Energy

PS.Chm.7.1

Classifying Matter by Composition

Materie besteht aus Atomen den kleinsten Einheiten der Materie und Molekülen, die durch Kombination von zwei oder mehreren Atomen gebildet werden. Aufgrund ihrer Zusammensetzung, kann die Materie in zwei Gruppen eingeteilt werden Reinstoffen und Gemischen. Laut ihrer Definition betrachten wir eine Materie als rein, wenn sie nur aus einer Komponente mit einer einheitlichen Zusammensetzung besteht.Nehmen wir zum Beispiel Wasserstoff. Wasserstoff ist nur aus Wasserstoffatomen gebildet. Ebenso besteht Wasser nur aus Wassermolekülen.Diese Zusammensetzungen variieren nicht von einer Probe zur anderen. Reine Substanzen können in zwei Typen eingeteilt werden Elemente und Verbindungen, je nachdem ob sie zerlegt werden können. Elemente sind reine Substanzen, die nicht durch chemische Reaktionen in einfachere Substanzen abgebaut werden können.Wasserstoff, zum Beispiel, ist ein Element. Verbindungen sind im Gegenteil Substanzen, die in ihre Bestandteile in chemischen Reaktionen zerlegt werden können. Wasser, zum Beispiel, auch eine reine Substanz, kann chemisch in zwei einfachere Substanzen zerlegt werden Wasserstoff und Sauerstoff das heißt, es ist eine Verbindung.Auf der Erde sind Verbindungen häufiger als reine Elemente weil die meisten Elemente leicht mit anderen Elementen reagieren. Zum Beispiel, Kreide mit der man an der Tafel schreibt, besteht aus Kalzium, Kohlenstoff und Sauerstoff;Zucker besteht aus Kohlenstoff, Wasserstoff, und Sauerstoff. Gemische im Gegensatz zu Reinstoffen, bestehen aus einer oder mehreren Komponenten.Der Anteil von Komponenten kann auch von Probe zu Probe variieren. Zum Beispiel ist Limonade ein Gemisch aus drei Komponenten Zitronensaft, Zucker und Wasser und ihre Proportionen können variiert werden, um das Getränk mehr oder weniger süß zu machen. Gemische selbst können in zwei Typen eingeteilt werden:homogen und heterogen, je nachdem wie die Substanzen darin zusammengesetzt sind.Eine homogenes Gemisch weist eine einheitliche Zusammensetzung auf und wirkt optisch überall gleich. Es wird oft als Lösung bezeichnet. Zum Beispiel, wenn ein Löffel Salz in Wasser gelöst wird, ergibt sich ein homogenes Gemisch, das in jedem Tropfen die gleiche Zusammensetzung hat.Ebenso ist Limonade eine homogenes Gemisch. In einem heterogenen Gemisch werden die Komponenten nicht gleichmäßig verteilt dadurch variiert die Zusammensetzung von Punkt zu Punkt. Zum Beispiel, wenn Sand mit Eisenspänen gemischt wird werden verschiedene Teile dieser Mischung wahrscheinlich unterschiedliche Mengen an Eisenspänen und Sand haben.Unabhängig davon, jedes Gemisch, ob homogen oder heterogen, kann durch physikalische Mittel in seine reinen Bestandteile zerlegt werden, ohne dabei die Identität der Komponenten zu ändern. Zum Beispiel kann Salz aus der Wasserlösung durch Erhitzen der Mischung bis zur Verdunstung, zurückgewonnen werden. Ebenso können die Eisenspäne von dem Sand mit einem Magneten getrennt werden.

materie nach zusammensetzung klassifizieren

<h4>Materie: Reinstoffe und Gemische</h4> Aufgrund seiner Zusammensetzung kann ein Stoff in zwei große Kategorien eingeteilt werden: Reinstoffe und Gemische. Ein Reinstoff weisteine durchgehend konstante Zusammensetzung mit einheitlichen Eigenschaften auf. Beispielsweise hat jede Saccharose-Probe, unabhängig von der Quelle, aus der sie isoliert wurde, die gleiche Zusammensetzung und die gleichen physikalischen Eigenschaften, wie Schmelzpunkt, Farbe und Süßkraft. Eine Mischung besteht aus zwei oder mehr Arten von Materie, die in unterschiedlicher Menge vorhanden sein können und durch physikalische Veränderungen, wie z.B. Verdunstung, voneinander getrennt werden können. Die Komponenten in einer Mischung behalten ihre eigene Identität. <h4>Reinstoffe: Elemente und Verbindungen</h4> Reinstoffe lassen sich in zwei Klassen einteilen: Elemente und Verbindungen. Reine Stoffe, die durch chemische Veränderungen nicht in einfachere Stoffe zerlegt werden können, werden Elemente genannt. Eisen, Silber, Gold, Aluminium, Schwefel, Sauerstoff und Kupfer sind Elemente. Als Verbindungen werden Stoffe bezeichnet, die sich durch chemische Veränderungen abbauen lassen. Bei diesem Abbau können entweder Elemente,andere Verbindungen oder beides entstehen. Quecksilber(II)-oxid, ein orangefarbener, kristalliner Feststoff, kann durch Hitze in die Elemente Quecksilber und Sauerstoff überführt werden. Beim Erhitzen der Verbindung Sacharose unter Ausschluss von Luft zerfällt sie in das Element Kohlenstoff und die Verbindung Wasser. Silber(I)-chlorid ist ein weißer Feststoff, der durch Lichtabsorption in seine Elemente Silber und Chlor zerfallen kann. Die Eigenschaften ?kombinierter? Elemente unterscheiden sich von denen im freien oder unverbundenen Zustand. Beispielsweise ist weißer kristalliner Zucker (Saccharose) eine Verbindung, die aus der chemischen Verbindung des Elements Kohlenstoff, das in einer seiner ungebundenen Formen ein schwarzer Feststoff ist, und den beiden Elementen Wasserstoff und Sauerstoff, die in ungebundenem Zustand farblose Gase sind, entsteht. Elementares Natrium, das ein weicher, glänzender, metallischer Feststoff ist, und Chlor, ein Element, das elementar als gelbgrünes Gas vorliegt, verbinden sich zu Natriumchlorid (Speisesalz), welches ein weißer, kristalliner Feststoff ist. <h4>Mischungen: Homogen und heterogen</h4> Eine homogene Mischung, auch Lösung genannt, weist eine einheitliche Zusammensetzung auf und erscheint optisch überall gleich. Ein Beispiel für eine Lösung ist ein Sportgetränk, das aus Wasser, Zucker, Farbstoffen, Aromen und Elektrolyten besteht, die gleichmäßig miteinander vermischt sind. Jeder Tropfen eines Sportgetränks schmeckt gleich, da jeder Tropfen den gleichen Anteil an Wasser, Zucker und anderen Bestandteilen enthält. Zu beachten ist, dass die Zusammensetzung eines Sportgetränks variieren kann – es könnte mit etwas mehr oder weniger Zucker, Aroma oder anderen Bestandteilen hergestellt werden und dennoch ein Sportgetränk sein. Weitere Beispiele für homogene Gemische sind Luft, Ahornsirup, Benzin und eine wässrige Salzlösung. Ein Gemisch mit einer von Ort zu Ort variierenden Zusammensetzung wird als heterogenes Gemisch bezeichnet. Ein Beispiel für eine heterogene Mischung wäre ein Salatdressing. Seine Zusammensetzung kann variieren, da es aus unterschiedlichen Mengen Öl, Essig und Kräutern zubereitet werden kann. Es ist nicht an jedem Ort innerhalb derMischung gleich – ein Tropfen kann hauptsächlich aus Essig bestehen, während ein anderer Tropfen hauptsächlich aus Öl oder Kräutern bestehen kann, da sich Öl und Essig trennen und die Kräuter absetzen. Weitere Beispiele für heterogene Mischungen sind Schokoladenkekse (wir können die einzelnen Bestandteile Schokolade, Nüsse und Keksteig sehen) und Granit (wir können Quarz, Glimmer, Feldspat und mehr unterscheiden). Jedes Gemisch, ob homogen oder heterogen, kann auf physikalischem Weg in reine Komponenten getrennt werden, ohne dass sich die ?Identität? der Komponenten ändert. Obwohl es knapp über 100 Elemente gibt, entstehen aus unterschiedlichen Kombinationen dieser Elemente Dutzende Millionen chemischer Verbindungen. Jede Verbindung hat eine spezifische Zusammensetzung und besitzt bestimmte chemische und physikalische Eigenschaften, die sie vonanderen Verbindungen unterscheiden. Weitergehend gibt es unzählige Möglichkeiten, diese Elemente und Verbindungen zu unterschiedlichen Mischungen zu kombinieren. Dieser Text wurde angepasst von <a href="https://openstax.org/books/chemistry-2e/pages/1-2-phases-and-classification-of-matter">Openstax, Chemistry 2e, Section 1.2: Phases and Classification of Matter.</a>

Materie nach Zusammensetzung klassifizieren

Materie: Reine Substanzen und Gemische
Entsprechend ihrer Zusammensetzung kann die Substanz in zwei große Kategorien eingeteilt werden – reine Stoffe und ...

Education

Lehre

JoVE Core

Chemie

Eins

Introduction: Matter and Measurement

Einleitung: Materie und Messung

KEY TERMS AND CONCEPTS

KERNBEGRIFFE UND KONZEPTE

matter: elements, compounds, and mixtures

Matter can be grouped by composition into pure substances and mixtures. A pure substance has a constant composition throughout and uniform properties. For example, any sample of sucrose has the same composition and the same physical properties, such as melting point, color, and sweetness, no matter where it is isolated from.

A mixture contains two or more kinds of matter in varying amounts. Its parts can be separated by physical changes, such as evaporation. The components keep their own identities, so the mixture is not a new substance in the same way a compound is.

Pure substances are divided into elements and compounds. Elements cannot be broken down into simpler substances by chemical changes. Iron, silver, gold, aluminum, sulfur, oxygen, and copper are examples of elements.

Compounds are pure substances that can be broken down by chemical changes. This breakdown may produce elements, other compounds, or both. Mercury(II) oxide can be heated to form mercury and oxygen, sucrose can break down into carbon and water when heated without air, and silver(I) chloride can be broken down by light into silver and chlorine.

The properties of combined elements are different from the properties of the elements in their free state. White crystalline sugar comes from carbon, hydrogen, and oxygen, but those elements look very different when uncombined. Free sodium is a soft, shiny metal, and free chlorine is a yellow-green gas, yet together they form sodium chloride, a white crystalline solid.

Mixtures can be homogeneous or heterogeneous. A homogeneous mixture, also called a solution, has a uniform composition and looks the same throughout. Sports drink is one example. It contains water, sugar, coloring, flavoring, and electrolytes mixed evenly, so each drop tastes the same. Its exact composition can still vary and remain a sports drink. Air, maple syrup, gasoline, and salt water are other homogeneous mixtures.

A heterogeneous mixture has a composition that varies from point to point. Italian dressing is one example, since the amounts of oil, vinegar, and herbs can differ and the parts may separate or settle. Chocolate chip cookies and granite are also heterogeneous mixtures because their different parts can be seen.

Any mixture, whether homogeneous or heterogeneous, can be separated into pure components by physical means without changing what the components are. There are just over 100 elements, but they combine in many ways to form tens of millions of compounds. Each compound has a specific composition and its own chemical and physical properties. Elements, compounds, and mixtures can combine in countless ways to make matter.

Matter: Elements, Compounds, and Mixtures

scientific laws and theories

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Scientific laws and scientific theories describe science in two different ways. A law is a concise verbal or mathematical statement that summarizes many experimental observations. It describes or predicts aspects of the natural world that stay the same under the same conditions. A scientific theory is different because it explains why natural events happen. It is a unifying principle that gives a well-supported and testable explanation for a broad set of observations. Strong theories are the...

the scientific method

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physical and chemical properties of matter

physical-and-chemical-properties-of-matter

Distinguishing Physical and Chemical Changes

Matter can be identified by its properties, which are the features that help us tell one substance from another. These properties fall into two main groups: physical properties and chemical properties. Understanding the difference helps explain how matter changes. A physical property is a feature of matter that is not linked to a change in chemical composition. Examples include density, color, hardness, melting point, boiling point, and electrical conductivity. Some physical properties can be...

what is energy?

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Energy is a property of matter that appears in many forms. On Earth, most energy starts with the Sun. Plants capture light energy from the Sun and use photosynthesis to turn it into chemical energy. That stored energy can then move through living things and materials in several ways. People get energy from plant foods, and wood or coal, which come from fossilized plants, can be burned to produce heat and electricity. Energy is defined as the ability to do work. Work happens when a force moves...

classifying matter by state

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States of matter help describe how matter behaves in chemistry. Matter is anything that has mass and takes up space. It is found everywhere, including air, water, soil, mountains, and even our bodies. The three common states on Earth are solid, liquid, and gas. A solid has a definite shape and a definite volume. Its particles, such as atoms or molecules, are packed very closely together and held in place by strong forces, so they only vibrate slightly. This tight arrangement makes solids...

measurement: standard units

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classifying matter by composition

Matter can be grouped by composition into pure substances and mixtures. A pure substance has a constant composition throughout and uniform properties. For example, any sample of sucrose has the same composition and the same physical properties, such as melting point, color, and sweetness, no matter where it is isolated from. A mixture contains two or more kinds of matter in varying amounts. Its parts can be separated by physical changes, such as evaporation. The components keep their own...

measurement: derived units

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SI units and derived units help describe physical properties in chemistry. The International System of Units, or SI system, uses agreed-upon base units for seven fundamental properties: length, mass, time, temperature, electric current, amount of substance, and luminosity. Units made by combining these base units are called SI-derived units. Speed is one example. If distance is measured in meters and time in seconds, the derived unit for speed is meters per second, or m/s. Miles per hour is...

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uncertainty in measurement: accuracy and precision

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uncertainty in measurement: significant figures

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key terms and concepts

Learn how matter is classified into elements, compounds, and mixtures. Explore pure substances, solutions, and examples like sports drink and Italian dressing.

Matter: Elements, Compounds, and Mixtures | JoVE K12

chemistry

JoVE Core Chemie erweckt allgemeine Konzepte der Chemie durch kompakte und leicht verständliche animierte Videolektionen zum Leben. Außerdem zeigen wir in den Videos Wissenschaftler in Aktion bei klassischen und neuartigen Forschungsexperimenten, wie sie heutzutage in Laboren weltweit durchgeführt wurden.

Matter and its Interactions

PS.Chm.1.1

Physical Science

PS.PSc.1.1

PS.PSc.1.3

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Ohio’s Learning Standards and Model Curriculum

Study Of Matter

Classification of matter

Physical Geology

Minerals

Crystallinity (crystal structure)

Virginia  Standards of Learning

HIgh School

CH.7

CH.7.a

Earth Science

ES.4

ES.4.a

PS.3

PS.3.a

Arizona Science Standards

High School

Earth and Space Science

HS.E1

HS.E1U1.12

HS.E1U1.13

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New Jersey Student Learning Standards for Science

Earth's Place in the Universe

HS-ESS1-2

Texas Essential Knowledge and Skills

CHEM.2

CHEM.2.A

Alabama Course of Study Science

Matter and Its Interactions

9-12.PS.3.5

9-12.PS.3.5.a

Next Generation Science Standards

HS-PS1-5

HS-PS1-4

Chemistry and Physics

IPC.7

IPC.7.C

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South Carolina College and Career Ready Science Standards

C-PS1-1

C-PS1-2

Earth and Space Science (ESS)

Earth’s Systems

E-ESS2-2.

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New York State Science Learning Standards

HS. Chemical Reactions

HS-PS1-2.

Georgia Standards of Excellence

SPS5.

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Clausius-Clapeyron Equation

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Phase Transitions: Sublimation and Deposition

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Heating and Cooling Curves

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First Law of Thermodynamics

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Thermochemical Equations

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Constant Pressure Calorimetry

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PS.Chm.7.2

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PS.Chm.7.3

Understand the relationship among pressure, temperature, volume, and phase.

Matter: Elements, Compounds, and Mixtures

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