The History of the Atom

Democritus (480 B.C.)

Sep 30, 1000

First person to purpose idea that matter was not infinitely divisble. Matter is composed of empty space through which atoms move.

Aristotle (322 B.C.)

Sep 30, 1001

Did not beleive that the nothingness of empty space could exist as Democritus had stated. Gained acceptance of his idea that denied the existent of atoms.

George Washington

Feb 22, 1732

1st President of the United States, George Washington, was born.

Antonie Lavosier

Oct 1, 1780

Found that mass is conserved in a chemical reaction. Law of Conservation of Mass.

Joseph Proust

Oct 1, 1799

Discoverd the law of defintie proportions.

John Dalton

Sep 30, 1800

All matter is composed of extremely small particles called atoms. All atoms of a given element are identical, having the same size, mass, and chemical properties. Atoms of specific element are different from those of any other element. Atoms cannot be created, divided into smaller particles, or destroyed. Different atoms combine in simple wholenumber ratios to form compounds. In a chemical reaction, atoms are separated, combined, or rearranged.

Amadeo Avagro

Oct 1, 1811

Hypothesis that equal volumes of different gases contain an equal number of molecules, provided they are at the same temperature and pressure.

Bowling Ball

Oct 2, 1862

Modern version of the bowling ball was invented.

William Crookes

Sep 30, 1869

Invented the cathode ray tube. https://www.youtube.com/watch?v=GzMh4q-2HjM

Telephone

Mar 10, 1876

Alexander Graham Bell invents the telephone.

Light Bulb

Oct 2, 1879

Thomas Edison filed a patent for an electric lamp with a carbon filament.

Coca Cola

Oct 2, 1886

The soda Coca Cola was invented by John Pemberton

Henri Becquerel

Oct 2, 1896

Discovered some chemicals spontaneously decompose and give off very pentrating rays. Found radiation. https://www.youtube.com/watch?v=GURSTwuX6Bc

J.J. Thomson

Sep 30, 1897

Concluded that the mass of the charged particle was much less than that of a hydrogen atom, The lightest known atom. In other words he found the electron. https://www.youtube.com/watch?v=IdTxGJjA4Jw

Max Planck

Sep 30, 1900

Concluded that matter can gain or lose energy only in small, specific amounts called quanta.

Albert Einstein

Oct 2, 1905

Video E=mc^2, energy is equal to mass multiplied by the speed of light squared. https://www.youtube.com/watch?v=hW7DW9NIO9M

Robert Millikan

Sep 30, 1909

Determinded charge of electron and was then able to calculate the mass of an electron.

Ernest Rutheford

Sep 30, 1911

Concluded that there was a tiny, dense region, which he called the nucleus, centrally located within the atom that contained all of an atom’s positive charge and virtually all of its mass. https://www.youtube.com/watch?v=8ar0CqT0Vwg

Henry Moseley

Sep 30, 1913

Discovered that atoms of each element contain a unique positive charge in their nuclei, or atomic number.

Niels Bohr

Sep 30, 1913

Proposed that electrons must occupy specific, quantized energy levels in an atom.

Louis deBroglie

Oct 1, 1926

Research on quantum theory and for his discovery of wave nature of electrons.

Erwin Schrodinger

Oct 1, 1926

Treated electrons in atoms as waves, quantum mechanical model of the Atom. Atomic model in which electrons are treated as waves is called the wave mechanical model. Attempts to describe the electron path around the nucleus. Predicted existence of atomic orbitals containing electrons.

Al Capone

Oct 18, 1931

Al Capone was convicted and sentenced to eleven years in federal prison, fined $50,000 and charged $7,692 for court costs, in addition to $215,000 plus interest due on back taxes.

James Chadwick

Sep 30, 1932

Concluded that the nucleus also contained another subatomic particle, a neutral particle called the neutron.

Werner Heiseberg

Oct 1, 1933

Concluded that it is impossible to make any measurement on an object without disturbing the object, at least a little.

World War 2

Sep 2, 1945

World War 2 ended on this day. Germany, Italy, and Japan were axis powers. Allied powers included Australia, Brazil, Canada, Newfoundland, New Zealand, South Africa, Soviet Union (from June 1941), United Kingdom, and United States (from December 1941).

Junior Mints

Oct 2, 1949

Junior Mints were invented by James O. Welch Company.

Corvette

Jun 30, 1953

First Corvette was built at General Motors facility in Flint, Michigan.

Facebook

Feb 4, 2004

Mark Zuckerburg invented Facebook.

Madam Curie

Oct 2, 2015

Radiation was not the outcome of some interaction of molecules but must come from the atom itself.This hypothesis was an important step in disproving the ancient assumption that atoms were indivisible.