Topic 2: Atoms, Elements & Compounds

Differences between elements, compounds and mixtures; types of substances and how they are classified

Protons, neutrons and electrons; relative charges and masses; proton number and nucleon number; electronic configurations of the first 20 elements; group and period relationships

Definition and notation of isotopes; same chemical properties explained; calculating relative atomic mass from isotopic abundances

Formation of cations and anions; ionic bonding; dot-and-cross diagrams; properties of ionic compounds; giant ionic lattice

Covalent bonding; dot-and-cross diagrams for simple molecules; properties explained by weak intermolecular forces

Diamond, graphite and silicon dioxide structures; relating properties to bonding; uses

Metallic bonding model; explaining electrical conductivity and malleability