UNIT 2 Flashcards
Who bombarded gold foil with alpha particles?
Ernest Rutherford
Who devised the first atomic theory?
John Dalton
Who developed the planetary model of the atom?
Ernest Rutherford
Who discovered the first subatomic particle?
JJ Thomson
Who based his model on “electron clouds”?
Erwin Schrodinger
Who first coined the term “atom”?
Democritus
Who discovered the nucleus?
Ernest Rutherford
Who devised the plum pudding model?
JJ Thomson
Who was the first to suggest electrons had a fixed energy?
Niels Bohr
Who said that all atoms of an element are identical in size, mass and other properties?
John Dalton
Who determined that the mass of an atom was concentrated in the center?
Ernest Rutherford
Who showed cathode rays are composed of negative particles?
JJ Thomson
Who had the FIRST idea of a basic indivisible particle?
Democritus
Who concluded that all elements contain electrons?
JJ Thomson
Who conducted an experiment using Cathode Ray Tubes?
JJ Thomson
Who conducted an experiment using Gold Foil?
Ernest Rutherford
The number of an element is the total number of which particles in the nucleus?
Protons
All atoms of the same element have the same ______.
number of protons
Isotopes of the same element have different ______.
numbers of neutrons and mass numbers
an atom that has gained or lost electrons and carries a net electrical charge is called an ______.
ion
