People Who Discovered Atoms
developed many lab techniques
Alchemists
tried to turn metal to gold
Alchemists
Proved and defined the idea of an element
Anton Lavoisier
took ideas from Robert Boyle and Democritus
Anton Lavoisier
believed that everything was made out of four elements
Aristotle
Atomos= indivisible
Democritus
all matter is made up of particles so small that they could not be cut any smaller.
Democritus
predicted the existence of unknown elements at the time and left spaces.
Dmitri Medeleev
First to organize all the known elements
Dmitri Mendeleev
organized based on atomic masses and chemical behavior of elements
Dmitri Mendeleev
# of protons=# of electrons
Ernest Rutherford
atom was mostly empty space, found protons inside the atom, ran into plump of protons, or also known as nucleus.
Ernest Rutherford
Created Gold Foil Experiment
Ernest Ruthford
discovered elements with green glow, created his model of the atom.
J.J. Thomson
discovered there was negatively charged elements in atoms.
J.J. Thomson
James Chadwick
James Chadwick
A compound is made up of 2 or more elements and are combined in a specific ratio
John Dalton
Different elements atoms are different
John Dalton
all elements are composed of atoms that cannot be divided
John Dalton
atoms cannot be created or destroyed in a chemical change.. they are merely rearranged
John Dalton
father of atomic theory
John Dalton
same elements atoms are identical
John Dalton
1st orbital = 2 electrons 2nd orbital= 8 electrons 3rd orbital= 18 electrons 4th orbital= 32electrons
Niels Bohr
closest to the nucleus electrons are least energy, farther to the nucleus has more energy.
Niels Bohr
First to propose the idea of element
Robert Boyle
Invented the cathode (Crookes) ray tube
William Crookes