Discovery of electron 1897 - J.J. Thomson (1856-1940) /thomson.html

Slides:

Advertisements

Similar presentations

Atomic Structure Discovery of the electron –In 1897, JJ Thomson, an English physicist began studying atomic structure using a cathode ray tube (see right)

Advertisements

Part II Discovers the Electron Experimented with cathode rays Took a glass tube and pumped most of the air out of it. Applied a high voltage that.

An atom is made of a nucleus containing protons and neutrons; electrons move around the nucleus. Section 2: Defining the Atom K What I Know W What I Want.

People, Experiments, Conclusions. Democritus – Ancient Greeks (5th century B.C.) believed in a small, indivisible particle – “atomos” Dalton – Modern.

Models of the Atom: A Historical Perspective

24-1 Physics I Class 24 e/m Ratio for the Electron.

Chapter 8 Atoms and Periodic Properties. Fig. 8.1 Computer generated model of a beryllium atom p n.

Instrumental Chemistry Chapter 11 Atomic Mass Spectrometry.

1 CHAPTER 5 The Structure of Atoms. 2 Fundamental Particles Three fundamental particles make up atoms:

The History of the Atom.

Inside the Atom.

The Law of Conservation of Mass

The Scientists of the Atomic Theory

Mass Spectrometer Mass spectrometere is a very powerful method to analyse the structure of organic compounds.

Stoichiometry Quantitative nature of chemical formulas and chemical reactions Chapter 3 (Sections )

What are important discoveries related to the structure of an atom?

Chapter 3 The History of the Atom. I. The Scientists and their Discoveries A.Democritus 1. Date = 400 B.C 2. Discovery = Theorized the smallest unit of.

The Parts of an Atom.

J.j. Thomson Atomic Model

Atomic Theory Timeline

Mullis1 Democritus ( B.C.) Democritus was one of a few Greek philosophers who believed that all matter in the world was made of of indivisible parts.

Chapter 32 - Modern Physics Rutherford Model of the Atom Bohr Model of Atom –Quantized Energy Levels –Atomic Spectra Quantized Energy levels and Electron.

ATOMIC THEORY. History of the Atom  feature=related feature=related.

Back ©Bires, 2002 Slide – The Discovery of Atomic Structure AP Chemistry Summer Work Chapter 2 Anyone who says that they can contemplate quantum.

Atoms, Molecules, and Ions Chapter 2 Atoms, Molecules, and Ions John D. Bookstaver St. Charles Community College St. Peters, MO  2006, Prentice Hall,

Early Experiments to Characterize the Atom 2. 4 Chapter 2 Atoms, Molecules, and Ions.

1.3 Atomic Theory 1. John Dalton’s atomic theory - Matter is made up of small particles called atoms - Atoms cannot be created, destroyed or divided.

History of the Atom Democritus Democritus: It was 400 BC when he came up with the idea that matter could not be divided indefinitely. This lead to the.

The Atomic Theory of Matter By Shaffer Lisle. The First Theories John Dalton’s proposed theories: Each element is composed of particles called atoms.

Modern Version of the Experiment: Using electricity, water is electrolyzed into its components, hydrogen and oxygen. Results: Water is always found to.

Atom : The smallest particle of an element that keeps all the properties of that element. Lesson: Old Dead Guys.

EARLY ATOMIC THEORY CHAPTER 3. THE ATOM: FROM PHILOSOPHY TO SCIENTIFIC THEORY 400 BC – Democritus came up with the idea of the ________ Nature’s basic.

Evolution of the Atomic Theory. Greek Philosophy (400 BC) Democritus “All matter is made of atoms” Philosophy is knowledge gained only by observation.

Student will learn: Relationship between light & electrons What produces color Electromagnetic Spectrum Readings Neils Bohr Model of Hydrogen Readings.

Atomic Theory Thomson Model of the Atom J. J. Thomson - English physicist Made a piece of equipment called a cathode ray tube. It is a vacuum tube.

Atomic theory = Dalton Electron discovery = JJ Thomson Electron charge = Millikan Nucleus discovery = Rutherford Neutron = Chadwick.

The Atom Chapters 4-5 Atomic Theories Democritus ~ 400 BC believed that atoms were indivisible and indestructible Dalton ~ 1800’s Developed through experiments.

John Dalton’s Atomic Theory  Elements composed of small particles called “atoms”  All atoms of a given element are the same, but different from other.

The Atomic Theorists.

The History of the Atom Democritus to Rutherford.

DEMOCRITUS ( B.C.) Atoms are indivisible, smallest particles.

Mass Spectrometry Relative atomic masses and the mass of individual isotopes can be determined using a mass spectrometer. The principle behind mass spectrometry.

Mixtures of Isotopes In nature, elements occur as a mixture of isotopes.In nature, elements occur as a mixture of isotopes. Average atomic mass = weighted.

Mass Spectrograph Physics Chapter 27 B. Mass spectrograph Adapted CRT/Thomson tube used to form and accelerate charged particles and measure their deflection.

Chapter 26 Electromagnetism. Mass of Electron Determined by J.J. Thomson Determined by the deflection of the electron in a cathode ray tube.

Historical Perspective of Atomic Discovery. Democritus Circa 400 BC A-tomfrom the Greek for “not-cut” Atomic theory had no scientific proof.

UNIT 2 Atoms, Molecules, and Ions. 1. Each element is composed of extremely small particles called atoms. 2. All atoms of a given element are identical.

Section 4.2 Defining the atom. The Atom What we know now: Definition: Atoms are the smallest particle of an element that retains the properties of that.

Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Table of Contents Chapter 3 Atoms: The Building Blocks of Matter.

Section 2: Defining the Atom

And Now, Let’s Talk About Dead Guys

History of the Atomic Model 2.1

Five Experiments You Should Know

Instrumental Chemistry

Mass Spectrometry.

History of the Atomic Model 2.1

History of the Atomic Model 2.1

Chapter 3- Atomic Structure

Chapter 3 Experiments of Thomson and Millikan

A sample is injected into the spectrometer and heated to a vapour.

History of the Atomic Model 2.1

Discovery of the Electron

e/m Ratio for the Electron

Scientists and Their Experiments

X Chapter 4 Test Review The Atomic Theory.

Discovery of the Atom.

Presentation transcript:

Discovery of electron J.J. Thomson ( ) /thomson.html (Kennedy, Chemistry Live!)

Mass spectrometry Sample converted to positive ions by collisions with a stream of high energy electrons on entering the spectrometer. Charged sample is accelerated using applied voltage Ions then passed into an evacuated tube and through a magnetic field. Magnetic field causes ions to be deflected by different amounts depending on their mass. Ions with the same mass-to-charge ratio hit the detector at the same spot. ( Brown, LeMay and Bursten, 9 th ed., p.45)

Determination of electron charge Robert Millikan (1868 – 1953)

Discovery of nucleus Ernest Rutherford ( )

Quantum Theory and the Atom Niels Bohr (1885 – 1962) posted/surprises-bohr.html