IB Chemistry HL 2.1.3 Ionic compounds
IB Chemistry HL 2.1.3 Ionic compounds
Recognise ionic compounds in exams by their lattice properties, and distinguish ionic attraction between ions from covalent bonds inside polyatomic ions.
How this is tested
- use melting point, conductivity and brittleness to identify an ionic lattice in a data table
- in Tl2SO4, S-O bonds are covalent within SO4^2-, but Tl+ to SO4^2- attraction is ionic
- stronger ionic attraction comes from higher charge and smaller ions, e.g. Li+ and O2-