# data[].attributes.body
In 1803, John Dalton developed a theory that stated that each element consisted of its own unique brand of invisible atom(s). He described these atoms to be "a ball like structure."

# data[].attributes.body
In 1897, after a series of experiments, JJ Thomson found that all atoms contain negatively charged subatomic particles or electrons.

# data[].attributes.body
In 1911, Ernest Rutherford found that the atom is mostly empty space, with nearly all of its mass concentrated in a tiny, positively charged central nucleus.

# data[].attributes.body
In 1913, Niels Bohr proposed a model of the atom in which the electron was able to occupy only certain orbits around the nucleus.

# data[].attributes.body
In 1932, James Chadwick proved the existence of neutrons - elementary particles without any electrical charge.