3.6 Intermolecular forces, electronegativity and bond properties

(a) Describe hydrogen bonding, limited to molecules containing N–H and O–H groups, including ammonia and water as simple examples; (b) use the concept of hydrogen bonding to explain the anomalous properties of H₂O (ice and water): its relatively high melting and boiling points, its relatively high surface tension, and the density of solid ice compared with liquid water.

Taught in: Hydrogen bonds: a special kind of attraction, Why ice floats and water boils high · 8 questions

Use the concept of electronegativity to explain bond polarity and the dipole moments of molecules.

Taught in: Polar bonds and whole-molecule dipoles · 4 questions

(a) Describe van der Waals' forces as the intermolecular forces between molecular entities other than those due to bond formation, and use 'van der Waals' forces' as a generic term for all intermolecular forces; (b) describe the types of van der Waals' forces: instantaneous dipole–induced dipole (id-id) forces, also called London dispersion forces, and permanent dipole–permanent dipole (pd-pd) forces, including hydrogen bonding; (c) describe hydrogen bonding and understand that it is a special case of permanent dipole–permanent dipole forces between molecules in which hydrogen is bonded to a highly electronegative atom.

Taught in: Hydrogen bonds: a special kind of attraction, Three ways molecules attract · 7 questions

State that, in general, ionic, covalent and metallic bonding are stronger than intermolecular forces.

Taught in: Bonds inside, attractions between · 4 questions