Name: from atomos to the modern atom
Uploaded: 2023-06-23T15:38:43.000Z
Duration: 1 min 17 s
Channel: JoVE

K12 Standards

Pennsylvania State Academic Standards

9-12

Earth and Space Science

Space Systems

3.3.9-12.C

Atomic Structure

모든 원소는 원자라고 하는 작은 입자로 구성되어 있습니다. 이러한 입자는 각 원소에 끓는점, 녹는점 및 밀도와 같은 고유한 물리적 및 화학적 특성을 부여합니다.
원소의 모든 원자는 동일한 속성을 갖지만 다른 원소의 원자와 다릅니다.
그러한 차이는 아원자 입자—양성자, 중성자, 전자—에 기인한다.
양성자와 중성자는 모두 각각 하나의 원자 질량 단위를 가진 원자 질량에 기여하는 반면 전자는 거의 무시할 수 있는 질량을 가지고 있습니다.
양성자와 중성자는 중심핵에 모여 있습니다. 원자 번호와 같은 양성자의 수는 특정 원소를 결정합니다.
양성자는 양전하를 띠고 중성자는 전하를 띠지 않았으므로 핵은 순 양전하를 띱니다.
음전하를 띤 전자의 구름이 핵에 끌립니다. 이 구름은 대부분 비어 있으며 원자 부피의 대부분을 구성합니다.
중성 원자는 동일한 수의 양성자와 전자를 포함하여 양전하와 음전하를 상쇄하고 순 전하를 생성하지 않습니다.

원자 구조

그리스 철학자 데모크리토스는 지구상의 모든 것이 그리스어로 나눌 수 없다는 뜻의 아토모스라는 작은 입자로 이루어져 있다고 주장했으며, 현대의 원자라는 용어는 이로부터 유래되었습니다. 19세기에 존 돌턴(John Dalton)은 오늘날에도 대체로 맞는 원자론을 제안했습니다. 그는 원자가 우리 주변의 세계를 어떻게 구성했는지 설명하기 위해 다섯 가지 가정을 제시했습니다. (1) 모든 물질은 무한히 작은 입자나 원자로 구성되어 있다. (2) 특정 원소의 모든 원자는 서로 동일하며 (3) 다른 모든 원소의 원자와 다릅니다. (4) 두 개 이상의 원소가 고정된 비율로 결합하여 화합물을 형성할 수 있습니다. (5) 원자는 화학 반응에서 생성되거나 파괴될 수 없지만 재배열되어 새로운 물질을 형성할 수 있습니다. Dalton은 물질을 구성하는 입자에 관해 부분적으로만 정확했습니다. 원자는 일반적인 화학적 또는 물리적 과정으로 더 이상 분해될 수 없지만, 세 개의 더 작은 아원자 입자로 구성됩니다. 아원자 구조에 대한 첫 번째 단서는 J.J. 톰슨은 전자를 발견했습니다. 과학자들은 원자의 전체 전하가 중성이라는 것을 알고 있었지만 톰슨의 '자두 푸딩 모델'은 그렇지 않았습니다. 원자의 발견은 음으로 하전된 입자의 존재에 관한 새로운 정보를 제공했으며, 이는 전자가 양으로 하전된 영역 전체에 박혀 있는 것이 발견되었음을 암시합니다. 나중에 어니스트 러더퍼드는 원자 질량의 대부분이 핵에 집중되어 있다는 것을 보여주는 실험을 수행했습니다. 여기서 양성자는 원자의 양전하를 차지하고 작은 음전하를 띤 전자가 공간의 대부분을 차지합니다. 핵 외부. 이것은 Thomson의 자두 푸딩 모델이 반증되었음을 입증했습니다. 1932년에 제임스 채드윅(James Chadwick)은 중성자가 원자에 존재하는 질량을 설명한다는 것을 발견했습니다. 현재 받아들여지고 있는 이론에 따르면, 양성자는 원자핵에서 발견되며, 양전하를 띠고, 각각 1원자질량단위(AMU)의 질량을 갖고 있습니다. 양성자의 수는 주기율표의 원자 번호와 동일하며 원소의 정체성을 결정합니다. 중성자는 핵에서도 발견됩니다. 그들은 전하를 갖고 있지 않지만 양성자와 동일한 질량을 갖고 있어, 원자의 원자 질량에 기여합니다. 전자는 구름 속의 핵 주위를 공전합니다. 이들은 음전하를 띠고 질량은 무시할 수 있으므로 원자의 전체 전하에 기여하지만 질량에는 기여하지 않습니다.

그리스 철학자 데모크리토스 (Democritus)는 지구상의 모든 것이 그리스어로 "나눌 수 없다"는 의미의 atomos라고 불리는 작은 입자로 구성되어 있다고 제안했습니다.

Education

교육

JoVE Core

Anatomy and Physiology

해부학 및 생리학

Unit 1

제1단원

Fundamentals of Chemistry

화학의 기초

KEY TERMS AND CONCEPTS

주요 용어 및 개념

from atomos to the modern atom

Atoms are the tiny building blocks of matter, and ideas about them go back to the Greek philosopher Democritus. He suggested that everything on Earth is made of atomos, a Greek word meaning &quot;indivisible.&quot; That idea later led to the modern word atom.

In the 19th century, John Dalton developed an atomic theory that is still largely correct today. He proposed five key ideas. All matter is made of tiny particles called atoms. Atoms of the same element are alike, and atoms of different elements are not. He also said that elements combine in fixed ratios to form compounds, and that atoms are not created or destroyed in a chemical reaction. Instead, they rearrange to make new substances.

Dalton’s model was only partly complete. Atoms cannot be broken down by ordinary chemical or physical processes, but they do contain smaller subatomic particles. The first major clue came from J. J. Thomson, who discovered the electron. At the time, scientists knew atoms were neutral overall, so Thomson’s plum pudding model suggested that negative electrons were spread through a positively charged material.

Later, Ernest Rutherford carried out an experiment that changed the atomic model. His results showed that most of an atom’s mass is packed into a central nucleus. In this model, protons provide the atom’s positive charge, and the tiny negative electrons take up most of the space outside the nucleus. This finding disproved Thomson’s plum pudding model.

In 1932, James Chadwick discovered the neutron, which explained the mass still present in the atom. In the accepted model today, protons and neutrons are in the nucleus. Protons have a positive charge and a mass of one atomic mass unit, or AMU, each. The number of protons equals the atomic number on the periodic table and defines the element. Neutrons have no charge, but they have about the same mass as protons, so they add to atomic mass. Electrons move in clouds around the nucleus. They have a negative charge and very little mass, so they affect the atom’s overall charge more than its mass.

From Atomos to the Modern Atom

what is matter?

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the periodic table and organismal elements

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atomic structure

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atomic weight

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electron behavior

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From Atomos to the Modern Atom | JoVE K12

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Louisiana Student Standards for Science

High School

Chemistry

Matter And Its Interactions

HS-PS1-1

Next Generation Science Standards

Earth’s Place in the Universe

HS-ESS1-3

south-carolina-college-and-career-ready-science-standards

South Carolina College and Career Ready Science Standards

Matter and Its Interactions

C-PS1-1

C-PS1-2

C-PS1-3.

motion-and-stability-forces-and-interactions

Motion and Stability: Forces and Interactions

C-PS2-6.

Georgia Standards of Excellence

Physical Science

SPS1.

Atomic Structure of atoms

the-principle-of-superposition-and-the-gravitational-field

The Principle of Superposition and the Gravitational Field

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Nuclear Fission

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3.3.9-12.A

Emission Spectra

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Metal Flame Emission

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Molecular Spectroscopy: Absorption and Emission

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Atomic Emission Spectroscopy: Instrumentation

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Atomic Absorption Spectroscopy: Radiation and Light Sources

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Students who demonstrate understanding can construct an explanation of the Big Bang theory based on astronomical evidence of light spectra, motion of distant galaxies, and composition of matter in the universe.  Clarification Statement: Emphasis is on the astronomical evidence of the red shift of light from galaxies as an indication that the universe is currently expanding, the cosmic microwave background as the remnant radiation from the Big Bang, and the observed composition of ordinary matter of the universe, primarily found in stars and interstellar gases (from the spectra of electromagnetic radiation from stars), which matches that predicted by the Big Bang theory (3/4 hydrogen and 1/4 helium).  Assessment Boundary:

3.3.9-12.B

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Flame Photometry: Overview

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The Greek philosopher Democritus proposed that everything on Earth is made up of tiny particles called atomos, Greek for &#34;indivisible,&#34; from which ...

Students who demonstrate understanding can communicate scientific ideas about the way stars, over their life cycle, produce elements.  Clarification Statement: Emphasis is on the way nucleosynthesis, and therefore the different elements created, varies as a function of the mass of a star and the stage of its lifetime.  Assessment Boundary: Details of the many different nucleosynthesis pathways for stars of differing masses are not assessed.

Tidal Forces

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3.3.9-12.D

From Atomos to the Modern Atom

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