intermolecular forces

What are London/ van der walls dispersion forces caused by?

Unenven distribution of electrons within atom, resulting in delta- and delta+ charge on either side.

Temporary dipole established and can induce a temporary dipole on another neighbouring atom

Random electron movement

Where do London dispersion forces occur?

Exist between all atoms.

How strong are van der walls forces?

Weak and easily broken, much weaker than covalent bonds.

Why do atoms with more electrons have a stronger boiling point?

They experience stronger London forces

When do permanent dipoles occur?

When two dipoles get close to each other they are attracted. They must be permanent (always have a difference in electronegativity)

When do hydrogen bonds occur?

When a hydrogen is between 2 electronegative atoms.

Lone pair of electrons and covalently bonded to a H atom.

Where is hydrogen bonding drawn/ how is it shown?

Between a lone pair and H

180^ angles

What is the strongest type of intermolecular bond?

Hydrogen bonds