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Proposed that matter exists in the form of a particle
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Proposed the atomic theory based on measured masses
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Created the first periodic table
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Found that the nucleous was small, dense , and positivley charged
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Discovered that cathode rays travel in straight lines, and made Crookes tube
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Discovered the electron
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Alpha particles are doubly ionized helium atoms
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Atoms have orbital shells with electrons
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Discovered the neutron
Plan projects on a visual timeline
Map milestones, phases, deadlines, and key events in one place so the sequence is easier to see and share. Timetoast is a timeline maker for work, school, research, and stories.