Atomic Model Flashcards
What did the Greeks name the particles matter was composed of?
Atomos
Meaning indivisible
Which scientist believed atoms were indivisible?
John Dalton
What were the rays Thompson discovered called?
Cathode rays
What were the particles Thompson discovered called?
Electrons
What charge to electrons have?
Negative
Describe the plum pudding model
The plum pudding model is an atomic model. The sponge is positive, and the negatively charged electrons sit in it like plums.
What charge did the alpha particles geiger and marsden fired at the gold foil have?
Positive
What did the fact that most of the particles went straight through the gold foil prove about the atom?
Most of it is empty space
How do we know that the mass is mostly concentrated in a nucleus?
Because some particles bounced straight back
Why were some alpha particles deflected at large angles?
The centre mass is positively charged and so repels the alpha particles
Who discovered the neutron?
James Chadwick
What did Bohr find out about electrons?
They are kept in energy levels
