2.3 Intermolecular Forces

Question 1

what are intermolecular forces

Answer 1

when interactions occur between two molecules and influence each other indirectly (not through covalent bonds)

Question 2

what is electrostatic interactions

Answer 2

they arise from permanent (formal) charges. (this is the same as ionic bonds)

a cation is attracted to a anion

Question 3

what are dipole-dipole interactions

Answer 3

they arise from permanent (partial) charges (polar molecules)

ie S- and S+ of two different molecules bond

Question 4

what is hydrogen bonding

Answer 4

it is a type of dipole-dipole interaction that is so common it gets its own name

the S+ on a hydrogen attached to a heteroatom
the partial S- is on another heteroatom

Question 5

what is a hydrogen bond acceptor and hydrogen bond donor

Answer 5

molecules that have a lone pair on an electronegative heteroatom are hydrogen bond acceptors

molecules that have a hydrogen attached to an electronegative heteroatom are hydrogen bond donors

Question 6

what are dispersion forces

Answer 6

they arise from temporary (partial) charges