TOPIC 1

• What is the correct scientific definition of isotopes?

  Atoms of the same element with the same number of protons but a DIFFERENT number of neutrons
• In ATOMS; the no. of protons and electrons will always be what? And why?

  Equal because atoms are neutral, whereas ions do possess a charge.
• Where should Mungo find the RAN + RAM in the periodic table? - and explain them.

  mass number is ABOVE the symbol. (The mass number will be bigger) and it represents protons + neutrons

  atomic number is BELOW the symbol.

  this represents the number of protons only.
• The nucleus of an atom will be what charge always and why?

  Positive, because electrons (negative) are in shells ORBITING the nucleus.
• How has atom theory developed?

  Dalton (1) -> Thomson (2) -> Rutherford (3) -> Bohr (4)

  1. Atoms as solid spheres
  2. Plum pudding model all sbclr particles within
  3. Nuclear atom with electrons in clouds
  4. Nuclear atom with electrons in shells