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🌟Valence electron vs Core electron

Electrons in an atom split into two roles. The outermost ones do the chemistry while the inner ones stay locked away.

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🌟Valence electron
  • Located in the outermost shell
  • Involved in chemical bonding
  • Determines an element's reactivity
  • Shown in Lewis dot diagrams
  • Lost, gained or shared in reactions
Core electron
  • Located in the inner, filled shells
  • Not involved in bonding
  • Tightly held by the nucleus
  • Shields valence electrons from full nuclear charge
  • Generally unchanged in reactions

Verdict

Valence electrons live in the outer shell and govern bonding and reactivity; core electrons stay buried inside, shielding the outer ones but not joining reactions.

Frequently asked

Which electrons take part in bonding?+

Valence electrons in the outermost shell are the ones involved in chemical bonding.

What do core electrons do?+

They shield valence electrons from the full pull of the nucleus but do not bond.

Where are valence electrons shown?+

In Lewis dot diagrams, which display only the outer-shell electrons.

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