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101
Democritus
- He believed that all matter consisted of extremely small particles could not be divided. He thought there were different type of atoms with specific properties.
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John Dalton
1) All matter is made of atoms. Atoms are indivisible and indestructible. 2) All atoms of a given element are identical in mass and properties 3) Compounds are formed by a combination of two or more different kinds of atoms. 4) A chemical reaction is a rearrangement of ato -
J.J. Thomson
he used a device that had a sealed glass tube which most of the air has been removed.there is a metal disk at each end of the tube. wires connect the metal disks to a source of electric current. when the current is turned on, one disk becomes negatively charged and thr other disk becomes positively charged. a glowing beam appears in the space between the disks. -
Hantaro Nagaoka
he believed that an atom had a central nucles and electrons floating around it. he compared it to the rings of satrun. -
Ernest Rutherford
he discovered that uraniun has fast moving particles. He condeucting an experement with gold foil to see if particles would move straight threw -
niels bohr
he foced on electrons. he said the arangement of the electons is the center piece of atoms. He said electrons have different engery levels like a stair case. -
Werner Heisenberg & Erwin Schrodinger
The electron cloud is a visual model of the probable locations of electrons in an atom. The probabilty of finding an electron is higher in the denser regions of the cloud. -
James Chadwick
newtrons- he wanted to show that netrons exestied.
