Chapter 11

Question 1

What force holds particles together in liquids?

Answer 1

intermolecular attractive forces

Question 2

What does increasing pressure or decreasing temerpature casue the liquid particles to do?

Answer 2

lock particles ina crystalline arrangement

Question 3

How can you transfomr a gas to a liquid?

Answer 3

temerpature of a gas decreases, average kinetic energy decreasing allowing the attractions between teh paeticles to draw the particles close together,

increasing the pressure

Question 4

As attractive forces get stronger what happens to the temerpature at which teh liquid boils?

Answer 4

increases

Question 5

What happens to the melting point as intermolecular forces increase?

Answer 5

increases

Question 6

What are the three types of intermolecualr forces?

Answer 6

dipersion forces, dipole-dipole attractions, hydrogen bonding

Question 7

What is dispersion froce

Answer 7

resulting from attraction between induce dipoles

Question 8

What does dipersion force depend on?

Answer 8

polarizability

Question 9

what is polarizability?

Answer 9

the ease with which the electron cloud of an atom or a molecule is distorted by an outside influence, inducing a dipole moment

Question 10

What does polarizability do as number of electrons increase?

Answer 10

increases

Question 11

What does polarizability do as volume increases?

Answer 11

increases

Question 12

What does dipersion force do as molecular weight increases?

Answer 12

increases

Question 13

What happens to boiling point as dipersion froces increase(get stronger)

Answer 13

increases

Question 14

Does linear molecules increase or decrease the dipersion forces?

Answer 14

increases

Question 15

Does spherical molecules increase or decrease the dipersion force?

Answer 15

decreases

Question 16

If a substance is hard to polarize what happens to the boling point?

Answer 16

decreases

Question 17

What are dipole-dipole interactions?

Answer 17

a force that becomes significant when polar molecules come in close contact with one another

Question 18

What effeces dipole-dipole interactions?

Answer 18

increaes polarity

Question 19

When dipole moment increases what does the boiling poiint do?

Answer 19

increase

Question 20

Which is bigger dipole-dipole interaction or disperison forces when the two molecules are the same size and shape?

Answer 20

dipole-dipole interactions

Question 21

Which is more domiant if one molecule is larger than another? (dipole-dipole moment or dispersion forces)

Answer 21

dipersion force

Question 22

What does boiling point do as you go down group 4A,5A,6A,and 7A elements?

Answer 22

increases

Question 23

What is hydrogen bond?

Answer 23

an attraction between a hydrogen atom attached to a highly electronegative atom and a nearby small electronegative atom in another molecule or chemicla group

Question 24

When electroegativity increases what does hydrogen bonding do?

Answer 24

increase

Question 25

What does hydrogen bonding make the molecules do in ice?

Answer 25

makes the molecules farther apart in ice than in liquid water causing ice to be more dense

Question 26

What is an ion-dipole force?

Answer 26

the force that exists between an ion and a polar molecule that possesses a permanet dipole moment

Question 27

Which intermolecular force is found in all susbtacnaes?

Answer 27

dispersion forces

Question 28

What kind of molecules is dipole-dipole interactions in?

Answer 28

All polar molecules

Question 29

What kind of molecules is hydrogen bonding in?

Answer 29

polar molecules containing OH, NH, or HF groups

Question 30

What kind of molecules is ion-dipole interactions found in?

Answer 30

ionic solids dissolved in polar liquids

Question 31

When the molecules of two substances have the same molecular weight and shape what is the dispersion force?

Answer 31

equal in the two substances

Question 32

When the molecule of two substance differ in molecular weight and there is no hydrogen bonding what is the disperison froces

Answer 32

dispersion forces tend to determine which substance has the stronger intermolecular atteactions

Question 33

when they have the same shape and the same molecular weight and they have hydrogen bonding How do you determine which one is stronger?

Answer 33

Which one has the most Hydrogens

Question 34

What is viscosity?

Answer 34

the resistance of a liquid to flow

Question 35

What happens to flow of a liquid when the viscoisty increases?

Answer 35

more slowly

Question 36

What does viscosity depend on?

Answer 36

attractive forces between molecules as well as their shape and flexibility

Question 37

As the length and flexibility of a molecule increases what happens to the viscoisty?

Answer 37

increases

Question 38

As molecular weight increases what happens to the viscosity?

Answer 38

increases

Question 39

What happens to the viscosity of a substance as the temerpature increases

Answer 39

decreases

Question 40

What is surface tension?

Answer 40

the energy required to increase the surface area of a liquid by a amount

Question 41

What are cohesive forces?

Answer 41

intermolecular forces taht bind similar molecules to one another

Question 42

What are adhesive forces?

Answer 42

intermolecular forces that bind a substance to a surface

Question 43

Why is there a mensicus in water?

Answer 43

due to the adhesive forces between the water and the glass being greater than the cohesive forces

Question 44

What is capilary action?

Answer 44

the proces by which a liquid rises in a tube

Question 45

What causes capillary action?

Answer 45

the combination of adhesion to the walls of the tube and cohesion between liquid particles

Question 46

Does adhesive forces increase or decrease teh surface tension?

Answer 46

increases

Question 47

When there is more carbons does it increase or decrease viscoisty?

Answer 47

increases

Question 48

What are phase changes?

Answer 48

Changes of state

Question 49

When a solid goes to liquid what is the name of the process?

Answer 49

fusion or melting

Question 50

When a solid changes to a liquid does the energy increase or decrease?

Answer 50

energy is added(endothermic)

Question 51

When a liquid changes to a solid what is it called?

Answer 51

freezing

Question 52

When a liquid changes to a solid does it gain or lose energy?

Answer 52

energy is released

Question 53

When a liquid changes to a gas what is it called?

Answer 53

vaporization

Question 54

When a liquid changes to a gas does it lose or gain energy?

Answer 54

gain energy

Question 55

When a gas goes to a liquid what is it called?

Answer 55

condensation

Question 56

When a gas goes to a liquid does it lose or gain energy?

Answer 56

loses energy

Question 57

When a gas goes to a solid what is it called?

Answer 57

Deposition

Question 58

When a gas goes to a solid does it lose or gain energy?

Answer 58

energy is released

Question 59

When a solid goes to a gas what is it called?

Answer 59

sublimation

Question 60

When a solid goes to a gas does it lose or gain energy?

Answer 60

energy added

Question 61

What is heat of fusion?

Answer 61

the enthalpy change, ∆H for melting a solid

Question 62

What does vapor pressure do as temeprature increases?

Answer 62

increases

Question 63

What is heat of vaporization?

Answer 63

the enthalpy change, ∆H for vaporization of a liquid

Question 64

What is heat of sublimation?

Answer 64

the enthalpy change, ∆H for vaporization of a solid

Question 65

When it is a diagnol line is it a phase change or heating up?

Answer 65

heating up

Question 66

When it is a solid line on the heating curve is it a phase change or temperature change?

Answer 66

phase change

Question 67

How do you find phase change?

Answer 67

n∆H

Question 68

How do you find specific heat?

Answer 68

mc∆T

Question 69

What is critical temperature?

Answer 69

the highest temperature at which a liquid phase can form

Question 70

What causes critical temperature to increase?

Answer 70

increase in magnitude of intrmolecular forces

Question 71

What is critical pressure

Answer 71

the pressure at which a gas at its critical temperature is converted to a liquid state

Question 72

As molecular weight or polarity increases what happens to the critical temperature and pressure

Answer 72

increases

Question 73

What is a supercritical fluid?

Answer 73

the state that exists when liquid and gas phases are indistinguishable from each other as the temp exceeds critical temp and the pressure exceeds critical pressure

Question 74

What is vapor pressure?

Answer 74

the pressure exerted by a vapor in equilibrum with its liquid or solid phase

Question 75

What is dynamic equilibrium?

Answer 75

a state of balance in which opposing process occur at the same rate

Question 76

What happens to the pressure molecules that are exerted as more molecules escape?

Answer 76

increase

Question 77

What is the boiling point of a liquid?

Answer 77

the temp where the vapor pressure equals the atmospheric pressure

Question 78

What is the vapor pressure at for normal boiling point?

Answer 78

1atm or 760 torr

Question 79

As boiling point increases what happens to the vapor pressure?

Answer 79

decreases

Question 80

As boiling point increases what happens to the intermoleculr forces?

Answer 80

become stronger

Question 81

What is pressure inversely propotional to?

Answer 81

temperature

Question 82

What is the equation to find vapor pressure

Answer 82

ln(P2/P1)=-∆Hvap/R(1/T2p 1/T1)

Question 83

What is a phase diagram?

Answer 83

a graphic way to summarize the conditions under which equlibria exist between teh different states of matter

Question 84

What does C represent on the phase diagram?

Answer 84

critical point critical pressure and temp

Question 85

What does the red curve represent on the phase diagram?

Answer 85

vapor pressure cuve

Question 86

What does the green curve represent on the phase diagram?

Answer 86

the sublimation curve

Question 87

What does the blue curve represent on the phase diagram?

Answer 87

melting curve

Question 88

What does the T represent on the phase diagram?

Answer 88

triple point

Question 89

What is a triple point?

Answer 89

the temp at which solid, liquid and gas phases coexist in equilibirum

Question 90

Temperature increases as you go which way on the phase diagram?

Answer 90

to the right

Question 91

As you move up the phase digram what happens?

Answer 91

the pressure increases

Question 92

Why is the curve of vapor pressure flipped on the H20 diagrma?

Answer 92

since the dneisty of solid is smaller then liquid

Question 93

Why is the vapor pressure line not as curved on the carbon dioxide phase diagram?

Answer 93

solid is more dense then liquid

Question 94

Where is sublimation located on the phase digram?

Answer 94

below critical pressure or critical point