history of the atom Flashcards
what did Democritus discover?
matter could be divided into the smallest possible piece
matter is?
what something is made up of
what can’t atoms do?
be created or destroyed
atoms are infinite in?
number, always moving and capable of joining together
what did Dalton discover in 1803?
matter is composed of indivisible atoms, all atoms of a given element are identical
what did thomson discover in 1897?
the electron and proposed the plum pudding model
what is the plum pudding model?
at atom is a sphere of positive charge with negatively charged electrons scattered throughout, like plums in a pudding
what did Rutherford discover in 1911?
the nucleus, proposed that atoms have a small,dense positive center with electrons orbiting around it
what did Bohr discover in 1913?
electrons orbit the nucleus in shells they can move between these levels by absorbing or emitting energy.
what did chadwick discover in 1932?
the neutron, a neutral particle found in the nucleus of an atom
don’t drink tasty berry red cocktails
Democritus, Dalton, Thomson, Bohr, Rutherford, Chadwick
