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Grade 8 Science Study Guide
Test date: Friday, March 4th
Person
Contribution/belief
John Dalton
-An English chemist, school teacher
-Believed that all elements are
composed of atoms
-It is impossible to divide or destroy an
atom
-formed the atomic theory model of the
atom
J.J. Thompson
-An English scientist
-he discovered the electron
-“plum pudding” model of the atom
Ernest Rutherford
-conducted a famous experiment called
the gold foil experiment
-his experiment showed us that atoms
are made of a small positive nucleus
-atoms are mostly empty space
-discovered the nucleus
Niels Bohr
-a Danish physicist
-he proposed a model of the atom that
is similar to the model of the solar
system
-electrons orbit the nucleus in “shells”
Democritus
-a Greek philosopher
-he made a mental model of the atom
Democritus cont.
-he believed atoms could not be divided
into smaller pieces
-he believed that the universe was
made up of empty space and tiny bits of
“stuff” called atoms
Issac Newton
-proposed a mechanical universe with
small solid masses in motion
Albert Einstein
-published the famous equation E=mc2
James Chadwick
-he discovered a neutral atomic particle
with a mass close to a proton
Anton Lavoisier
-He questioned- could matter be
created or destroyed?
-His famous experiment was burning
paper
-From his work came the law of
conservation of matter
A small particle that makes up most
types of matter
Atom
Electron
Law of conservation of matter
Matter
An invisible particle with a negative
charge around the nucleus of an atom
Matter is not created or destroyedmatter only changes form
Anything that has mass and takes up
space
Neutron
A neutral particle in the nucleus of an
atom
Nucleus
The positively charged central part of
an atom
Proton
Gold foil experiment
Positively charged particle in the
nucleus of an atom