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Electronic Structure

Electrons have fixed positions in atoms called shells or energy levels. These shells (or energy levels) go around the atom's nucleus.

Filling electron shells

Filling electron shells

  • Electrons fill an atom's shells in order of increasing energy.
    • The closer a shell is to the nucleus, the lower its energy level, so the first shell that is filled is the closest to the nucleus.
Electron configuration

Electron configuration

  • Electron configuration tells us how an atom's electrons are organised.
  • The inner shell (closest to the nucleus) can have a maximum of 2 electrons and the next two shells can have a maximum of 8 electrons.
  • Any extra electrons are then put into a fourth shell.
Jump to other topics
1

States of Matter

2

Elements, Compounds & Mixtures

3

Atomic Structure

4

The Periodic Table

5

Chemical Formulae, Equations & Calculations

6

Bonding

7

Electrolysis

8

Groups of the Periodic Table

9

The Atmosphere

10

Reactivity Series

11

Metal Extraction

12

Acids & Alkalis

13

Chemical Tests

14

Physical Chemistry

15

Organic Chemistry

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