Name: kinetic molecular theory and gas behavior
Uploaded: 2020-09-03T13:38:26.000Z
Duration: 2 min 43 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

NC K-12 Science Standard Course of Study

9-12

Chemistry

Energy

PS.Chm.7.3

basic-postulates-kinetic-molecular-theory-particle-size-energy

Basic Postulates of Kinetic Molecular Theory: Particle Size, Energy, and Collision

気体の法則が 理想気体のさまざまな性質の 関係を まとめたものであるのに対し 分子動力学理論は気体が なぜ法則に 従うのかを説明しています この理論はいくつかの仮定や 想定に基づいています 第一の前提は 気体の粒子の 大きさは無視できるほど 小さいということです 気体は その寸法よりも はるかに大きな距離を隔てた 小さな粒子で構成された 大部分が空の空間です それらを合わせた体積は ガスが含まれる総体積に対して 無視できる程度のものです 固体や液体が 粒子間の間隔が近いために 非圧縮性であるのとは対照的に 気体は非常に圧縮性があります 気体の粒子は ランダムな方向に 直線に沿って 一定の運動状態にあります 他の粒子と衝突したり 容器の壁に衝突したりした 場合にのみ その経路が変化します 第二の前提は ガス粒子は完全に弾性を持った 衝突をするということです 気体粒子は 互いにくっつくことなく衝突して 跳ね返ってきます これは ビリヤードの ゲーム中のビリヤードの ボール同士の衝突に 例えることができます 気体の粒子が衝突すると お互いエネルギーを交換しますが エネルギーの正味の 損失はありません 言い換えれば システムの 総エネルギーは一定です 気体の粒子は 常に動いているので 運動エネルギーを持っています したがって 第三の仮定では 気体の平均運動エネルギーは その絶対温度（ケルビン）に 比例するということになります つまり 運動エネルギーは 温度とともに増加し その結果 粒子は より速く移動することになります 温度が高くなると 粒子の速度は速くなります 逆に 温度が下がると 粒子の運動エネルギーも低下し 粒子の動きは遅くなります ある温度では 分子量に関係なく すべての気体は 同じ平均運動 エネルギーを持っています 運動エネルギーは 質量×速度の二乗です したがって 異なるガスが 同じ平均運動エネルギーを 持つためには そのガス粒子は 異なる平均速度で 移動しなければなりません したがって 重いガスは 平均速度が低く 軽いガスは平均速度が 高くなります 例えば ヘリウムとネオンは 同じ温度であれば 同じ平均運動エネルギーを 持っています しかし 質量の違いから ネオン原子の方が ヘリウム原子よりも 動きが遅いのです

分子運動論：基本前提

経験的なものである理想気体の状態方程式は、気体の巨視的な特性間の関係を確立することにより、気体の挙動を記述します。 たとえば、 シャルルの法則では、体積と温度は直接関連すると規定されています。 したがって、気体は一定の圧力で加熱すると膨張します。 気体の法則は、巨視的な性質が相互にどのように変化するかを説明していますが、その背後にある根拠については説明していません。 
 
 分子運動論は、圧力や温度変化などの条件が変化したときに、分子レベルまたは原子レベルで気体粒子がどうなるかを理解するのに役立つ微視的モデルです。 1857 年に ルドルフ・クラウジウスが完全で満足のいく形の理論を発表しました。その理論は気体の挙動に関する何百もの実験的観察に基づいて開発された公理によって、さまざまな気体の法則を効果的に説明します。 
 
 この理論の際立った特徴は次のとおりです。 
 
 <ol>
 <li>気体は、連続的に運動する粒子（原子または分子）で構成されており、直線的に移動し、他の分子や容器の壁に衝突した場合にのみ方向が変化します。 
 標準的な温度と圧力で気体アルゴンの試料を検査します。 それによると、体積の0.01%しか原子が占めておらず、 2 つのアルゴン原子間の平均距離は 3.3 nm （アルゴンの原子半径は 0.097 nm ）です。 原子間距離は、原子自体の寸法よりもはるかに大きいです。 </li>
 <li>気体を構成する分子は、それらの間の距離と比較して無視できるほど小さいです。 したがって、すべての気体粒子の総体積は、容器の総体積に対して無視できます。 粒子は、質量はあるが体積が無視できる「点」と見なされます。 </li>
 <li>容器内の気体によって生じます。圧力は、気体分子と容器の壁との衝突によって生じます。 </li>
 <li>気体分子は、互いにまたは容器の壁に引力や反発力を与えないため、衝突は弾性的です（エネルギー損失を伴わない）。 
 弾性衝突中、衝突した粒子間でエネルギーが伝達されます。 なので、粒子の平均運動エネルギーは一定に保たれ、時間とともに変化することはありません。 </li>
 <li>気体分子の平均運動エネルギーは、気体のケルビン温度に比例します。 
 すべての気体は、分子量に関係なく、同じ温度で同じ平均運動エネルギーを持ちます。 </li>
 </ol>
 
 この文章は <a href="https://openstax.org/books/chemistry-2e/pages/9-5-the-kinetic-molecular-theory">、 Openstax, Chemistry 2e, 第 9.5 章 The Kinety-Molecular Theory から引用</a>したものです。

経験的な理想気体方程式は、気体の巨視的特性間の関係を確立することにより、気体の振る舞いを記述します。対して。。。

Education

JoVE Core

化学

Gases

気体

KEY TERMS AND CONCEPTS

主要用語と概念

kinetic molecular theory and gas behavior

Kinetic molecular theory explains gas behavior at the particle level. It gives a microscopic model for what happens when pressure or temperature changes. Gas laws describe how macroscopic properties change, but they do not explain why those changes happen.

The theory was put into a complete form by Rudolf Clausius in 1857. It was built from hundreds of experimental observations about gases. Those observations helped explain the different gas laws through a few basic postulates.

One key idea is that gases are made of particles, either atoms or molecules, that move constantly. They travel in straight lines until they collide with other particles or with the walls of a container. A sample of argon gas at standard temperature and pressure shows that the particles take up only a tiny part of the total volume. The average distance between two argon atoms is much larger than the size of the atoms themselves. Because of this, gas particles are treated as points with mass but negligible volume.

Gas pressure comes from collisions between gas molecules and the walls of the container. The particles do not attract or repel each other, and they do not interact with the container walls through such forces. For that reason, their collisions are elastic, which means no energy is lost in the collision. Energy can still be transferred between colliding particles, but the average kinetic energy stays constant over time.

The average kinetic energy of gas particles depends on the kelvin temperature of the gas. It is proportional to temperature. At the same temperature, gases with different molecular masses have the same average kinetic energy.

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mixtures of gases: dalton's law of partial pressures and mole fractions

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basic postulates of kinetic molecular theory: particle size, energy, and collision

Kinetic molecular theory explains gas behavior at the particle level. It gives a microscopic model for what happens when pressure or temperature changes. Gas laws describe how macroscopic properties change, but they do not explain why those changes happen. The theory was put into a complete form by Rudolf Clausius in 1857. It was built from hundreds of experimental observations about gases. Those observations helped explain the different gas laws through a few basic postulates. One key idea...

kinetic molecular theory and gas laws explain properties of gas molecules

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Gas Pressure Patterns in Kinetic Molecular Theory

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key terms and concepts

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Kinetic Molecular Theory and Gas Behavior | JoVE K12

chemistry

JoVE Core 化学は、簡潔で理解しやすいアニメーションビデオレッスンを使用して、一般的な化学の概念を生き生きとしたものにします。さらに、活動する科学者のビデオでは、現在世界中の実験室で行われている古典的そして独創的な研究・実験をお見せします。

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Ohio’s Learning Standards and Model Curriculum

Interactions Of Matter

Gas laws

Tennessee Academic Standards

High School

Matter and Its Interactions

CHEM1.PS1.5

Virginia  Standards of Learning

HIgh School

CH.6

CH.6.b

Physical Science

PS.2

PS.2.c

Arizona Science Standards

HS+C.P1

HS+C.P1U1.3

Texas Essential Knowledge and Skills

CHEM.10

CHEM.10.A

Alabama Course of Study Science

9-12.C.1.4.e

9-12.C.4.7

Florida Department of Education

SC.912.P.10

SC.912.P.10.5

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New York State Science Learning Standards

HS. Structure and Properties of Matter

HS-PS1-9.

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Heating and Cooling Curves

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Use models to explain how changes in energy affect the arrangement and movement of the particles in solids, liquids, and gases, as well as the relative strengths of their intermolecular forces.

PS.Chm.7.1

Energy Basics

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Chemical changes and their accompanying ...

First Law of Thermodynamics

Energy Conservation

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Internal Energy

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Quantifying Heat

Thermal Energy&#160;

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Quantifying Work

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Enthalpy

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Thermochemical Equations

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Constant Pressure Calorimetry

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Constant Volume Calorimetry

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PS.Chm.7.2

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Kinetic Molecular Theory and Gas Behavior

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