Atomic Theory Timeline

Historical Events

Gutenberg Printing Press 1448

1448

Discovery of the Americas 1492

1492

Reformation of the Catholic Church 1527

1527

Galileo convicted of heresy 1633

1633

Declaration of Independence 1776

1776

Forst transcontinental railroad in US 1850

1850

Civil War 1861

1861

Assassination of Archduke Ferdinand 1914

1914

Bolshevik Revolution 1917

1917

Treaty of Versailles 1919

1919

Bombing of Pearl Harbor 1941

1941

First cellular phone 1973

1973

Initial concept for the internet 1989

1989

Other Scientists that made significant contributions

Antoine Lavoisier- law of conservation of mass; father of modern chemistry 1772

1772

Joseph Priestley- discovered oxygen, carbon monoxide, and nitrogen dioxide 1774

1774

Alessandro Volta- electrochemical cell and batteries 1800

1800

Michael Faraday- electricity and electro chemistry 1821

1821

Louis Pasteur- pasteurization process 1848

1848

Alfred Nobel- dynamite, Nobel prize 1867

1867

Henri Becquerel- radioactivity 1896

1896

Marie Curie- radioactivity 1898

1898

Guglielmo Marconi- radio 1901

1901

Sir Frederick Banting- isolated insulin 1921

1921

Philo Farnsworth- TV 1934

1934

Wallace Carothers- neoprene and nylon 1935

1935

Leo Szilard- nuclear chain reactions and atomic bomb 1942

1942

Kary Mullis- polymerase chain reaction 1983

1983

Scientists that contributed to modern atomic theory

John Dalton 1803

1803

Dalton came up with the atomic theory which states that all matter was composed of small indivisible atoms, atoms of a given element possess unique characteristics and weight, and there are three different types of atoms.

Eugen Goldstein 1886

1886

Goldstein is known as the discoverer of protons. He also did experiments with cathode ray tubes.

J.J. Thompson 1897

1897

Thomson discovered the electron in 1897. He also concluded that electrons had a mass that was 1000 times smaller than a hydrogen atom.

Ernest Rutherford 1898-1910

1898 - 1910

In 1898 Rutherford discovered alpha and beta rays in uranium radiation. in 1910 he came up with the concept of the nucleus.

Max Planck 1900

1900

Planck is the originator of the quantum theory, which helps with understanding the atomic and subatomic processes.

Robert Millikan 1909

1909

Millikan was an american physicist who determined the charge on an electrons using charged oil drop experiments.

Henry Moseley 1913

1913

Moseley determined the number of positive charges in the nucleus by measuring the wavelength of the x-rays given off by certain metals.

Neils Bohr 1913

1913

Bohr came up with the theory that electrons only travel in certain successively larger orbits. He also determined that the outer rings hold more electrons than the inner rings. He also determined that when an electron jumps from an outer orbit to an inner one, they emit light.

Albert Einstein 1916

1916

Einstein came up the the general theory of of relativity and the photon theory of light and the theory of gravitation He also contributed to the theory of radiation and statistical mechanics.

Louis de Broglie 1924

1924

De Broglie introduced the theory of particle-wave duality.

Erwin Schrodinger 1926

1926

Schrodinger invented wave mechanics, which are used in quantum physics.

Werner Heisenberg 1927

1927

Heisenberg came up with the uncertainty principles and developed the operator methods for the solution of quantum mechanical problems.

James Chadwick 1932

1932

James Chadwick proved the existence of neutrons and contributed to the successful controlled fissioning of Uranium-235. He also eventually contributed to the development of the atomic bomb.