Timeline: Chemistry Timeline

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Democritus

Democritus was the first person to believe matter is not infinitely divisible. He also believed atoms could not be created, destroyed, or further divided

Oct 5, 1492

Columbus lands in the Bahamas

Spanish explorer Christopher Columbus lands in the Bahamas.

Oct 5, 1759

Benjamin Franklin invents the lightning conductor

Oct 5, 1766

John Dalton

John Dalton believed all matter is composed of extremely small particles (atoms) and all atoms are identical. Also, he thought atoms cannot be destroyed or created.

Oct 5, 1778

Antonie Lavosier

Antonie Lavosier, or the “Father of modern chemistry” recognized/named oxygen and hydrogen and also helped construct the metric system.

Oct 5, 1787

U.S. Constitution Written

Oct 5, 1799

Joseph Proust

Joseph Proust discovered the law of constant composition.

Oct 5, 1808

Amadeo Avagadro

Amadeo Avagadro is known for Avogadro’s Law, stating the relationship between the masses of the same volume of different gases correspond to the relationship between their respective molecular weights.

Oct 5, 1860

Abraham Lincoln becomes president of the United States

1860- Abraham Lincoln becomes president of the U.S.

Oct 5, 1861

William Crookes

Discovered thallium

Oct 5, 1863

Battle of Gettysburg

Oct 5, 1871

Ernest Rutherford

Ernest Rutherford discovered alpha and beta rays, set laws of radioactive decay, and identified alpha particles as helium nuclei. https://www.youtube.com/watch?v=Xb9KnwadI6Y

Oct 5, 1879

Thomas Alva Edison creates the electric light bulb

Oct 5, 1890

Max Planck

Max Planck found a deduce relationship between the energy and the frequency of radiation.

Oct 5, 1897

J.J Thomson

J.J Thomson showed that cathode rays consist of particles, electrons that carry electricity. He also concluded electrons are part of the atom https://www.youtube.com/watch?v=IdTxGJjA4Jw

Oct 5, 1898

Madame Curie

Madame Curie discovered radioactivity.

Oct 5, 1903

Henri Becquerel

Henri Becquerel discovered radiology with Marie Curie.

Oct 5, 1905

Albert Einstein

Albert Einstein worked with Brownian movement and developed a statistical molecular theory of liquids. https://www.youtube.com/watch?v=l-1Z2wi2uSA

Oct 5, 1910

Robert Millikan

Robert Millikan proved quantity is constant for all electrons and demonstrated the atomic structure of electricity.

Oct 5, 1913

Henry Moseley

Henry Moseley published the results of his measurements of the wavelengths of the x-ray spectral lines of multiple elements by atomic number.

Oct 5, 1913

Niels Bohr

Niels Bohr proposed a theory for the hydrogen atom based on quantum theory saying electrons move around nucleus. The heory could explain why atoms emitted light in fixed wavelengths. https://www.youtube.com/watch?v=ZkNPBy2i0ss

Oct 5, 1920

19th Amendment ratified, women were given the right to vote

Oct 5, 1924

Louis deBrogile

Louis deBroglie discovered the wave nature of electrons and suggested that all matter has wave properties.

Oct 5, 1925

Werner Heisenberg

Werner Heisenberg created theory of quantum mechanics

Oct 5, 1926

Erwin Schrodinger

Erwin Schrodinger formulated wave equation that accurately gave the energy levels of atoms.

Oct 5, 1932

James Chadwick

James Chadwick showed that in the reaction, a neutral particle with a mass about that of a proton was emitted. Discovered the neutron. https://www.youtube.com/watch?v=73JJRLd8Yio