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1 Atomic Structure

Cambridge AS Level Chemistry (9701) · 3 topics

Particles in the atom

Structure of the Atom An atom consists of a very small, dense nucleus at its centre, surrounded by a large region of mostly empty space in which electrons are…
Proton number, nucleon number and isotopes

Isotope Notation Isotopes are represented using standard nuclear notation, where the mass number appears at the top left and the atomic number at the bottom…
Electrons, energy levels and ionisation energy

Shells, Sub-shells and Orbitals Shell (Principal Energy Level) A main energy level occupied by electrons, described by the principal quantum number n (n = 1, 2,…