This definitions covers Key Definitions within Electronic Configuration for GCSE Chemistry. Revise Electronic Configuration in Atomic Structure for GCSE Chemistry with 24 exam-style questions and 24 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 7 of 12 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Topic position
Section 7 of 12
Practice
24 questions
Recall
24 flashcards
📖 Key Definitions
Electron shell (energy level): A region around the nucleus where electrons are found, each shell holding a maximum number of electrons (2, 8, 8...).
Electronic configuration: The arrangement of electrons in shells around the nucleus, written as numbers separated by commas, e.g., 2,8,1.
Outer shell electrons (valence electrons): The electrons in the outermost occupied shell — these determine the chemical properties and reactivity of an atom.
Period: A horizontal row in the periodic table; the period number equals the number of occupied electron shells.
Group: A vertical column in the periodic table; the group number equals the number of electrons in the outer shell.