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Newton proposed a mechanical universe with a small masses in motion
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He proposed an "atomic theory" with spherical solid atoms based upon measurable properties of mass
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He studied the effect of electricity and developed the laws of electrolysis.
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He built the cathode ray tube.
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He classified elements into 6 families by there valence.
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He arranged the elements into 7 groups. He discovered the periodic law, properties of elements "were periodic functions of their atomic weights."
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He discovered that cathode rays had the following properties: travel in straight lines from the cathode, cause glass to fluoresce, impart a negative charge to objects they strike, are deflected by electric fields and magnets to suggest a negative charge, cause pinwheels in their path to spin indicating they have mass.
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He used CRT to study canal rays
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He proposed electrons
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Using a CRT, he observed that nearby chemicals glowed. Further experiments found very penetrating rays coming from the CRT that were not deflected by a magnetic field. He named them x-rays
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He discovered some chemicals spontaneously decompose and give off very penetrating rays when studying the effect of x-rays on photogenic film
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He used CRT to experimentally determine the charge to mass ratio of an electron= 1.759 x 10.8 coulombs/gram. He also studies canal rays and found they were associated with the proton H+
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He studied radiation from uranium and named them alpha and beta. He estimated atom site and concluded mass was concentrated in the nucleus
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She studied uranium and thorium and called their decay process radioactivity. She and her husband Pierro also discovered the radioactive elements polonium and radium
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He used an idea of quanta to explain hot glowing matter
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He observed spontaneous disintegration of radioactive elements into variants he called isotopes. He made initial calculations on energy released during decay.
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He postulated a saturnian model of an atom with white flat rings of electrons revolving around a positively charged particle
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He discovered that inert gasses has a stable electron configuration which led to their chemical inactivity
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He discovered E=mc^2
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He developed an electrical device. The tube clicked when it hit the alpha particles
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Oil drop experiment determined the charge e=1.602 x 10^-19 and the mass m =9.11 x 10^-28 gram of an electron
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Using alpha particles as atomic bullets, probed the atoms in a piece of thin gold foil. He established that the nucleus was very dense, very small and positively charged. He assumed that the electrons were located outside of the nucleus.
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Using x ray tubes, determined the charges on the nuclei of most atoms. He wrote the atomic number of an element is equal to the number of protons in the nucleus. This work was used to recognize the periodic table based upon atomic number instead of atomic mass
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He discovered the existence of isotopes through he use of a mass spectrograph
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He developed an explanation of atomic structure that underlies regularities of the periodic table of elements. His atomic model had atoms built up of successive shells of electrons
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He discovered that electrons had a dual nature similar to both particles and waves
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He described atoms by means of formula connected to the frequencies of spectral lines. He proposed a principle of indeterminacy which is you cannot know both the position and velocity of a particle
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They built an early linear accelerator and bombarded lithium with protons to produce alpha particles
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He viewed electrons as continuous clouds and introduced "wave mechanics" as a mathematical model of the atom
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He proposed anti-particles . Anderson discovered the anti-electron (positron) in 1932 and Segre/Chamberlain detected the anti-proton in 1955..
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Using alpha particles discovered a neutral atomic particle with a mass close to a proton. Thus was discovered the neutron.
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Conducted experiments verifying that heavy elements capture neutrons and form unstable products which undergo fission. This process ejects more neutrons continuing the fission chain reaction.
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Synthesized 6 transuranium elements and suggested a change in the layout of the periodic table.
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Conducted the first controlled chain reaction releasing energy from the atoms nucleus.
