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He stated that the universe is made of tiny, invisible atoms that can't be destroyed and that differ in size, shape, and temperature.
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Newton understood that atoms move and 'swim' around.
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He came up with Dalton's theory.
1. Matter is made up of extremely small atoms.
2. Atoms are indivisible and indestructible.
3. Atoms of an element are identical in size and chemical props.
4. Atoms are different depending on the element.
5. In Chemical Reactions, atoms separate then combine and/or rearrange. -
Arranged elements into 7 groups with similar properties. He discovered that the properties of elements "were periodic functions of the their atomic weights". This became known as the Periodic Law
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Discovered the electron by experimenting with the cathode ray which is negatively charged.
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Marie Curie discovered the radioactivity part of the periodic table.
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Hans Geiger was a German nuclear physicist best known for his invention of the Geiger counter, a device used for counting atomic particles, and for his pioneering work in nuclear physics with Ernest Rutherford.
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His oil drop experiment helped to quantify the charge of an electron, which contributed greatly to our understanding of the structure of the atom and atomic theory.
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Rutherford overturned J.J. Thomason's theory with a Gold Foil experiment and discovered atoms have a small charged nucleus.
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Discovered that the frequency of X-Ray Radiation has a precise mathematical relationship to the element's atomic number.
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Bohr studied the structure of atoms, he realized electrons orbit.
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Described atoms by means of formula connected to the frequencies of spectral lines. Principle of Indeterminancy - you can not know both the position and velocity of a particle
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James Chadwick bombarded beryllium atoms with alpha particles. An unknown radiation was produced. Chadwick interpreted this radiation as being composed of particles with a neutral electrical charge and the approximate mass of a proton. This particle became known as the neutron
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Austrian physicist who worked on radioactivity and nuclear physics. Otto Hahn and Meitner led the small group of scientists who first discovered nuclear fission of uranium when it absorbed an extra neutron; the results were published in early 1939.
