Strength Of Van Der Waals forces

There are two types of intermolecular forces, one of them is Van Der Waals (VDW) forces.  Form the pictures below Van Der Waals are divided into 2 other types of intermolecular forces which call Dipole-dipole forces and London Dispersion Forces



The strength of VDW forces depends on molecular size, shape and polarity. As you can see above (on right side), I draw a chart for my student on how to identify which molecules having a higher boling point than the others. From the chart, the most important factors that affects boling point in VDW is the molecular size (calculate the Mr), the bigger the size (Mr) the greater the boling point. This chart has help my students to identify and arrange the molecules according to their boiling point more clearly. Hope that this will help you too !