Atomic structures

• Isotopes have different numbers of neutrons but the same number of protons.
• What is the relative charge and relative mass of a proton?

  +1 charge, 1 relative mass
• What is the relative mass and relative charge of a neutron?

  Relative mass: 1 Relative charge: 0
• What is the relative mass and relative charge for an electron?

  Relative mass: 1 / 1800 ( or almost 0) Relative charge: -1
• What is this model called?

  Plum pudding model.

  
• How was the Rutherford model created?

  Alpha particles were fired at a thin gold sheet. Rutherford expected small deflections, but there were some big deflections and 1 in 8,000 came back.
• What did Rutherford conclude about his experiment?

  • Most alpha particles passed straight through, so most of the atom is empty space
  • Positive alpha particles are repelled, so the nucleus must be positively charged
  • The nucleus must be small as only a few alpha particles were deflected