C1: DEVELOPMENT OF THE ATOMIC MODEL

Question 1

What was the plum pudding model?

Answer 1

-sphere of +ve charge with -ve electrons embedded in it

Question 2

What was Rutherfords scattering experiment?

Answer 2

-beam of alpha particles fired at a thin sheet of gold foil

Question 3

What observations did Rutherford make? What did these observations tell scientists?

Answer 3

1)-OBSERVATION: most particles passed straight through the foil
-CONCLUSION: most of the atom is empty space

2)-OBSERVATION: some particles were deflected at different angles
-CONCLUSION: centre of the atom is +vely charged

3)-OBSERVATION: some particles were reflected straight back
-CONCLUSION: mass is concentrated in the centre of the atom

Question 4

What was Bohr’s contribution to the model of the atom?

Answer 4

Bohr discovered energy levels/shells

Question 5

What was Chadwick’s contribution to the model of the atom?

Answer 5

Chadwick discovered neutrons