Doc 400 B.C. Democritus’ atomic theory posited that all matter is made up small indestructible units he called atoms.
Orlando 1704 Isaac Newton theorized a mechanical universe with small, solid masses in motion.
Kuwesi 1803 John Dalton proposed that elements consisted of atoms that were identical and had the same mass and that compounds were atoms from different elements combined together.
Isabella 1832 Michael Faraday developed the two laws of electrochemistry.
Ismeal 1869 Dmitri Mendeleev created the periodic table.
Aidan 1873 James Clerk Maxwell proposed the theory of electromagnetism and made the connection between light and electromagnetic waves.
Michael 1879 Sir William Crookes’ experiments with cathode-ray tubes led him to confirm the work of earlier scientists by definitively demonstrating that cathode-rays have a negative charge.
John (X) 1886 E. Goldstein discovered canal rays, which have a positive charge equal to an electron.
Nico 1895 Wilhelm Roentgen discovered x-rays.
Nicolas 1896 Henri Becquerel discovered radiation by studying the effects of x-rays on photographic film.
Isiah 1897 J.J. Thomson determined the charge to mass ratio of electrons.
Shane 1898 Rutherford discovered alpha, beta, and gamma rays in radiation.
Lianah 1898 Marie Sklodowska Curie discovered radium and polonium and coined the term radioactivity after studying the decay process of uranium and thorium.
Lenoyshka 1900 Max Planck proposed the idea of quantization to explain how a hot, glowing object emitted light.
Saryeliz 1903 Hantaro Nagaoka proposed an atomic model called the Saturnian Model to describe the structure of an atom.
Julian 1906 Hans Geiger invented a device that could detect alpha particles.
Emily 1914 H.G.J. Moseley discovered that the number of protons in an element determines its atomic number.
Kennedy 1922 Niels Bohr proposed an atomic structure theory that stated the outer orbit of an atom could hold more electrons than the inner orbit.
Kelis 1923 Louis de Broglie proposed that electrons have a wave/particle duality.
Kierra 1932 James Chadwick discovered neutrons, particles whose mass was close to that of a proton.