-
Period: to
Atomic Theories
-
Isaac Newton
Isaac Newton thought that the universe was full of small solid masses that are moving all the time. The way that he became famous was by discovering gravity and laws of gravity. Isaac said that the atoms are held together with attractions which also is known as forces. Isaac also had the theory of light that it was made out of small particles -
John Dalton
Dalton said that the atoms of other elements could be well known by the differences in their atomic weights. He presented his theory in 1803 to the Royal Institution. He also listed a couple of ideas:
- All matter is composed of atoms
- Atoms cannot be made or destroyed
- All atoms of the same element are identical
- Chemical reactions occur when atoms are rearranged
- Compounds are formed from atoms of the constituent elements -
Ernest Rutherford
Ernest’s atomic theory is that the atom has a nucleus with positive particles and it is surrounded by negative particles which are called electrons. His atomic theory says that the nucleus is the mass of the atom and the other parts of the atom are nothing. Ernest did his research with his gold foil experiment. His gold foil experiment was just firing the radioactive particles through thin metal and then spotting them with screens covered with zinc. -
J.J Thompson
J.J Thomson used vacuum tube that has one or more electrons and its called cathode tube and Thomson used it for his experiments. Thomson said that a model of the atom is a circle of positive matter where electrons are moving by electrostatic forces. -
Niels Bohr
Niels Bohr won the Nobel Price in 1922 for doing research on the atomic structure theory. He said that the outer orbit of an atom could hold more electrons than the inner orbit in his atomic structure theory. Bohr’s research said that he understood that an electron could orbit the nucleus but only in separate orbits which wouldn’t give off radiation. Niels Bohr structure was Rutherford's atomic theory but Bohr found more details on the atoms. -
James Chadwick
James Chadwick worked on Ernest Rutherford's atomic theory at Cambridge. James Chadwick discovered the neutral particle and it was named neutron. He discovered the 3rd particle of an atom. Ernest Rutherform knew that protons wasn't the only particle in the nucleus.
