Changes to the Atomic Model

Which is the best description of the Plum Pudding Model?

• A sphere of positive charge with tiny negative charges inside.

• A positive nucleus with electrons orbiting it.

• A lump of negative charge containing smaller positive charges.

• Protons and neutrons in a nucleus with electrons orbiting on shells.

Ernest Rutherford fired (a)   particles at thin gold foil.

As some alpha particles were deflected, it proved that...

• the nucleus was negatively charged

• there were electrons orbiting the nucleus

• the nucleus was relatively large and positively charged

• atoms were very small

Which of these was proof that atoms are mostly empty space?

• Some alpha particles passed straight through the foil.

• Some alpha particles were deflected by a small angle.

• Very few alpha were deflected back towards the source.

Describe the modern (Bohr) Model of the atom.