Isotopes and Development of the Atom Models

Question 1

What is an isotope?

Answer 1

Isotopes are atoms of the same element with different number of neutrons

Question 2

The plum pudding model
- who created it and when?
- what did it suggest?

Answer 2

• JJ Thomson in 1897
• suggested that an atom was a ball of positive charge with negative electrons throughout it

Question 3

Alpha particle scattering experiment ( nuclear model)
- who created it and when?
- what did it show?

Answer 3

• Ernest Rutherford in 1909
• showed that the mass of the atom was concentrated in its centre, which was charged

Question 4

The adapted nuclear model
- who created it and when?
- what did it show?

Answer 4

• Niels Bohr in 1913
• the nuclear model adapted to add electrons orbiting the nucleus at different distances