alpha scattering experiment

Question 1

what did the ancient greeks believe about atoms?

Answer 1

they made up everything and that they were tiny spheres that can’t be divided

Question 2

when were electrons discovered?

Answer 2

1897

Question 3

what did the discovery of electrons tell scientists?

Answer 3

atoms have an internal structure

Question 4

what model was made after electrons discovered?

Answer 4

plum pudding model

Question 5

what is the plum pudding model?

Answer 5

An atom is a ball of positive charge with negative electrons embedded in it.

Question 6

how was the plum pudding model proved to be incorrect?

Answer 6

the alpha scattering experiment. this was where gold foil (only a few atoms thick) had tiny alpha particles fired at it (positive charge). scientists found most particles passed through without changing direction. some deflected and some bounced straight back off gold foil.

Question 7

what did the alpha scattering experiment show?

Answer 7

as most particles passed straight through it meant atoms are mainly empty space. because some were deflected that meant the atom must have a positive charge (repelled). those that bounced straight back showed centre must contain great deal of mass (nucleus)

Question 8

what was the plum pudding model replaced with?

Answer 8

the nuclear model, with mostly empty space and a positive nucleus where mass is focused. around the edge are the electrons