Atoms Flashcards
What is the Plum Pudding Model?
Balls of positive charge with negative electrons randomly placed throughout
Who discovered electrons
JJ Thomson
Who created the PPM
JJ Thomson
Who suggested atoms were tiny balls
John Dalton
What was the alpha scattering experiment
Alpha particles were fired at a sheet of gold metal
What was the conclusions of the Alpha Scattering Experiment
Majority of the atoms mass must be concentrated at the centre
The centre must have a positive charge to repel the positive alpha particles
Majority of the atom must be empty space
What is the nuclear model
Positive nucleus with a cloud of negative electrons
Who discovered electrons orbiting the nucleus
Neils Bohr
Who discovered neutrons
James Chadwick
When were neutrons discovered
1932
When was the alpha scattering experiment
1909
What is the current model of the atom called
Bohr model
What is the current model of the atom
Positive nucleus containing positive protons, neutral neutrons an negative electrons orbiting the nucleus
What is the radius of an atom
1 x 10^-10 m
What happens when atoms absorb EM radiation
Electrons move to a higher energy level further from the nucleus
What happens when atoms release EM radiation
Electrons move to a lower energy level closer from the nucleus
