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406
Democritus
he was born in the city of abider in trace an Ionian colony of teos. he is known for today for his formulation of. an atomic theory of the universe.Democritus was wealthy and spent his inheritance on traveling so that he could learn from other cultuers -
Period: 406 to
time line
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John Dalton
John was born in eagles field England on September 6,1766.John Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass. he introduced he atomic theory into chemistry and for his research into color blindness. John dalton was a queer -
Dalton Atomic Theory
Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass. -
J.J. Thomson
He was born on December 18,1856 in Cheetham hill, England J.J Thomson discovered that the electron by experimenting with Crookes or cathode ray tube he demonstrated that cathode rays were negatively charged he also studied positively charged particles in neon gas.he attend trinity college at Cambridge -
gold foil experiment
The Geiger–Marsden experiments were a landmark series of experiments by which scientists discovered that every atom has a nucleus where all of its positive charge and most of its mass is concentrated. -
plum pudding atomic model
Thomson's model showed an atom that had a positively charged medium, or space, with negatively charged electrons inside the medium. -
Rutherford model
discovered that there are two types of radiation, alpha and beta particles, coming from uranium -
Niels Bohr
Niels Bohr was born on October 7, 1885, in Copenhagen, Denmark.Niels Bohr proposed a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well defined quantities. Electrons should move around the nucleus but only in prescribed orbits. bohr model shows he atom as a small positively charge. bohr was also a philosopher and a promoter of scientific resech -
Bohr planetary model
The Bohr Model is a planetary model in which the negatively charged electrons orbit a small, positively charged nucleus similar to the planets orbiting the sun (except that the orbits are not planar). -
Erwin Schrodinder
Erwin Schrodinder was born on August 12 1887 in Vienna,austria. Erwin was a noted theoretical physicist and scholar who came up with a ground breaking wave equation for electron movement.Schrodinder used mathematical equations to describe the likelihood of finding an electron in a certain position. he won a Nobel prize -
Ernest Rutherford
Ernest Rutherford was born in rural spring grove on the South Island of New Zealand on august 30 1871.He discovered that there are two types of radiation, alpha and beta particles, coming from uranium. He found that the atom consists mostly of empty space, with its mass concentrated in a central positively charged nucleus. -
Quantum Mechanical model
The quantum mechanical model is based on quantum theory, which says matter also has properties associated with waves -
Electron cloud model
The electron cloud model says that we cannot know exactly where an electron is at any given time, but the electrons are more likely to be in specific areas. These areas are specified by orbitals. -
James Chadwick
Chadwick was born in cheesier England on 20th of October in 1891. chadwick was british physicist was was awarded the 1935 Nobel prize in physics for his discovery of neutron in 1932. Chadwick bombarded berylium atoms with alpha particles. he inspired the U.S government to begin serious atomic bomb research efforts. -
cathode ray tube
Summary. J.J. Thomson's experiments with cathode ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons
