Size of the Nucleus

Specification Point 1.5:
  • Describe the nucleus of an atom as very small compared to the overall size of the atom.
  • The nucleus is located at the centre of the atom.
  • It is an extremely small region of space compared to the overall size of the atom.
  • To put this into perspective, if an atom were magnified to the size of a football stadium, then:
    • The nucleus would be the size of a small pea at the centre of the pitch where kick-off takes place.
    • The electrons would be orbiting the pea at the outermost seats of the stadium.
    • In between the nucleus and the electrons is empty space.

Mass of the Nucleus

Specification Point 1.6:
  • Recall that most of the mass of an atom is concentrated in the nucleus.
  • Electrons have a much smaller mass than protons and neutrons, which are packed very densely into the nucleus.
  • This means that rather than being evenly spread out throughout the atom, virtually all of an atom’s mass is concentrated inside the nucleus.

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Morgan Curtin Chemistry

Author: Morgan

Morgan’s passion for the Periodic Table begun on his 10th birthday when he received his first Chemistry set. After studying the subject at university he went on to become a fully fledged Chemistry teacher, and now works in an international school in Madrid! In his spare time he helps create our fantastic resources to help you ace your exams.