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Democritus
Denocritus discovered that matter is made up of small particles. he used logical thinking to discover this. -
Antonie Lavoisier
Antonie discoverd that matter is made out of H2O. also that the conservation of math, particles cant be made or destroid. Diamonds are graphite both forms of carbon by burning each to make carbon dioxide -
John Dalton
John's theory states that all matter is composed of tiny particles called atoms, they showed that diffrent gases placed in the tubes generated streams of particles and conducted a current, he proved this by experimenting with water and how it vaporates into gas in the structure of matter. -
JJ Thomson, Plucker, and Cooks
they discoverd that atoms contain smaller particles, They experimented with a series of obsevations of cathode ray tubes. -
Marie Curie
Marie's achievements include a theory of radioactivity techniques for isolating radioactive isotopes and the discovery of two elements, polonium and radinm. -
Robert Millikan
Robert determend the unit charge of the electron in 1909 with his oil drop ecperiment allowing for the calculation of the mass of the electron and hte positivly charged atoms. -
Ernest Rutherford
Ernest wanted to see if alpha particles could pass through gold foil, He then experimented with high-speed, light weight atoms called alpha particles, To bombard very thin pieces of gold foil. -
Niels Bohr
Niels discover that the electrons move around the nuecleus. Niels discoverd this by using info about nature of the emission of light by heated objects to update Rutherford's model. -
James Chadwick
James identified the third imporortant subtomic particle called the neutron. James used data from toliot and Rutherford's exsperiment