Intermolecular Forces

Question 1

Types of intermolecular forces

Answer 1

charges,

partial charges, induced dipoles

Question 2

Which types of interactions are pairwise additive?

Answer 2

ion and dipole interactions, dispersion forces

Question 3

Which types of interactions are not pairwise additive?

Answer 3

induced charge

Question 4

What do interacting molecules depend on?

Answer 4

• Different molecules have different dependencies on separation ( r ) of interacting molecules
=> strongly depends on distance, short range in nature
=> ion-ion interactions are weakest distance dependence, long range in nature.

Question 5

Give examples of non directional interactions

Answer 5

charge-charge,

van der waals

Question 6

Give examples of interactions which are not pairwise additive

Answer 6

charge induced dipole, dipole induced dipole,

carbon-pi

Question 7

Give examples of interactions with bond energies greater than 100kJ/mol

Answer 7

charge-charge,
charge-dipole,
hydrogen bonding

Question 8

What are the two parts of van der waal?

Answer 8

• London dispersion - attractive forces that occur when instantaneous dipoles in electron clouds around each molecule interact favourably
• exchange-repulsion - defines molecular shape