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The Atom
Discovery of the Atom and subatomic particles
Question | Answer |
---|---|
What 2 chemicals are used to demonstrate the particulate nature of matter? | Ammonia and Hydrochloric Acid |
3 ideas proposed by John Dalton: | 1: All matter is made up of atoms 2: These atoms are indivisible 3: They cannot be created or destroyed |
Discovered Cathode rays | William Crookes |
Discovered Cathode rays were made up of negative particles | JJ Thomson |
Discovered the quantity of the charge on an electron | Robert Milikans |
Thomson's Plum Pudding Theory | Atoms consisted of a large positive sphere with negative electrons embedded in it. |
Discovered the Nucleus | Ernest Rutherford |
Type of radiation Rutherford used, firing it at what metal? | Alpha radiation at gold foil |
Rutherfords new model of the atom | Rutherford proposed the atom was made up of mainly empty space with a solid positive core at its nucleus. |
Discovered the Proton | Also Ernest Rutherford |
Discovered the Neutron | James Chadwick |
Radiation used by Chadwick, firing at what metal? | Alpha particles at Beryllium |
Mass of an electron | 1/1838 |