Exam 1

Question 1

What are intermolecular forces?

Answer 1

attractive forces between molecules

Question 2

What are intramolecular forces?

Answer 2

forces that hold atoms together in a molecule

Question 3

Are intermolecular or intramolecular forces weaker?

Answer 3

intermolecular forces

Question 4

What is a major determining factor in boiling point, melting point, heat of vaporization and heat of fusion?

Answer 4

intermolecular force

Question 5

if a molecule is in a solid state…

Answer 5

interactive force > kinetic energy

Question 6

if a molecule is in liquid state…

Answer 6

interactive force and kinetic energy are about equal

Question 7

if a molecule is in gas state…

Answer 7

kinetic energy > interactive force

Question 8

What happens to the boiling point when the atomic number goes up?

Answer 8

boiling point increases

Question 9

What happens to the attraction of atoms as they get bigger?

Answer 9

stronger attraction

Question 10

What happens to boiling/melting point as the attraction gets stronger?

Answer 10

the boiling point and melting point both are higher

Question 11

What is the London Dispersion Force (LDF)?

Answer 11

intermolecular force between non polar molecules or atoms caused by presence of temporary dipoles

Question 12

What happens to LDF when molecule size increases?

Answer 12

LDF increases

Question 13

What is the weakest of all intermolecular forces?

Answer 13

London Dispersion Force

Question 14

What is dispersion?

Answer 14

a momentary shift in electron density

Question 15

How are temporary dipoles created?

Answer 15

a momentary shift in electrons

Question 16

What are the two main factors that affect the strength of dispersion factors?

Answer 16

atom size and atom shape

Question 17

What is dipole-dipole interaction?

Answer 17

force present between polar molecules

Question 18

What is a hydrogen bond?

Answer 18

an H+ atom bonded to an O, F, or N atom (highly electronegative)

Question 19

What is the stronger dipole-dipole interaction?

Answer 19

a hydrogen bond

Question 20

What happens to molar mass if you decrease boiling point?

Answer 20

molar mass decreases

Question 21

What is an ion-dipole interaction?

Answer 21

attractive force between an ion and molecule that has a permanent dipole

Question 22

What is a sphere of hydration?

Answer 22

cluster of water molecules surrounding an ion in an aqueous solution

Question 23

How does a sphere of hydration form?

Answer 23

ion dipole interaction

Question 24

What is sublimation?

Answer 24

a phase change from solid to gas