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Atomic Theory Timeline PDF: Democritus to John Dalton and Cool Models

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fuzzie duck

2/3/2023

Chemistry

Structure of the Atom and the History of the Atom Timeline

Atomic Theory Timeline PDF: Democritus to John Dalton and Cool Models

The atomic theory timeline showcases the evolution of our understanding of atomic structure, from Democritus' concept of "atomos" to Niels Bohr's planetary model. This progression highlights key contributions from scientists like John Dalton, J.J. Thomson, and Ernest Rutherford, each refining our atomic model over time.

  • Democritus introduced the idea of indivisible particles called "atomos" in 460 BC
  • John Dalton proposed that all elements are composed of atoms in the early 19th century
  • J.J. Thomson discovered electrons and developed the "plum pudding" model
  • Ernest Rutherford established the concept of a nuclear atom in 1911
  • Niels Bohr introduced the planetary model of the atom in 1913, explaining electron orbits
...

2/3/2023

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Chemistry

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Feb 3, 2023

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Atomic Theory Timeline PDF: Democritus to John Dalton and Cool Models

The atomic theory timelineshowcases the evolution of our understanding of atomic structure, from Democritus' concept of "atomos" to Niels Bohr's planetary model. This progression highlights key contributions from scientists like John Dalton, J.J. Thomson, and Ernest Rutherford, each refining... Show more

Structures of an Atom
Key
Eletrons
-Protons
-Nuetrons
O-Nucleus
-Orbit/Shell/clouds
Electrons - Negative Charge, floating around in orbits
N

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Structures of an Atom and Historical Timeline

This page provides a comprehensive overview of the atomic structure and a historical timeline of atomic theory. It begins with a detailed explanation of the key components of an atom and then delves into the contributions of various scientists to our understanding of atomic structure over time.

The structure of an atom is clearly outlined, identifying its key components:

  • Electrons: Negatively charged particles that orbit the nucleus
  • Protons: Positively charged particles found in the nucleus
  • Neutrons: Particles with no charge but with mass, located in the nucleus
  • Nucleus: The central part of the atom, containing protons and neutrons
  • Orbits/Shells/Clouds: The regions where electrons are found around the nucleus

Definition: The nucleus is described as the "center of the atom" and likened to the "brain of the cell," emphasizing its crucial role in atomic structure.

The atomic theory timeline presented on this page showcases the evolution of our understanding of atomic structure:

  1. Democritus 460BC460 BC: Introduced the concept of "atomos" as tiny, indivisible particles that vary in size and shape.

Highlight: Democritus' atomic theory laid the foundation for future atomic models, despite being proposed over two millennia ago.

  1. John Dalton 176618441766-1844: Developed the atomic theory stating that all elements are composed of atoms, and atoms of the same element are identical in mass and size.

Example: Dalton's theory explains the composition of compounds like H2O waterwater.

  1. J.J. Thomson 185619401856-1940: Discovered the electron and proposed the "Plum Pudding Model" of the atom.

Vocabulary: The Plum Pudding Model describes negatively charged electrons embedded in a positively charged sphere, similar to raisins in plum pudding.

  1. Ernest Rutherford 187119371871-1937: Proposed the Nuclear Atom model in 1911, suggesting that electrons orbit around a dense, positively charged nucleus.

Quote: Rutherford is dubbed the "Father of the Nuclear age" for his groundbreaking work on atomic structure.

  1. Niels Bohr 188519621885-1962: Introduced the Planetary Atom model in 1913, explaining that electrons orbit the nucleus at high speeds, preventing them from falling into it.

Example: Bohr's model is compared to planets orbiting the sun, providing a familiar analogy for understanding atomic structure.

This comprehensive overview of atomic models and the atomic theory timeline provides students with a clear progression of scientific understanding, from the earliest concepts to more sophisticated models of atomic structure.

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This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

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Anna

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I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

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Brad T

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David K

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The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

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Marco B

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This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

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