Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CHEM 119 > Unit 4: Liquids > Flashcards

Unit 4: Liquids Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

define intermolecular attractive forces

A
  • exist between any two molecules
  • some are stronger than others
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

are intermolecular forces generally stronger or weaker than chemical bonds

A

weaker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

define miscibility

A

the property that describes two substances that will mix together (dissolve in one another)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

which molecules are miscible and which are immisible

A
  • miscible: polar and polar, nonpolar and nonpolar
  • immiscible: polar and nonpolar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is an easy way to remember miscibility rules

A

like dissolves like

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

define ion-dipole interactions

A

ionic solid dissolved in polar solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

define dipole-dipole interactions

A

polar solute dissolved in polar solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the 4 types of dipole-dipole interactions

A
  • attraction on top of each other (double attraction)
  • attraction from end to end (single attraction)
  • repulsion on top of each other (double repulsion)
  • repulsion from end to end (single repulsion)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is the relationship between strength of polar bonds and strength on dipole-dipole interactions

A

more polar substances exhibit stronger dipole-dipole interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

define hydrogen bonds

A
  • dipole-dipole interactions when H is bonded with N, O, or F
  • the H will interact with other atoms or molecules along with the N, O, or F that it’s bonded with
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

are hydrogen bonds strong or weak

A

unusually strong

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

are hydrogen bonds actual bonds

A
  • no
  • just interactions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

explain why H makes hydrogen bonds when bonded with N, O, or F

A
  • N, O, and F are very electronegative so they pull electrons strongly to their side
  • H become very positive and interacts with other atoms or molecules to satisfy electrons requirements
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

explain how hydrogen bonds impact the density of ice

A
  • hydrogen bonds in water when frozen create lots of holes in the structure, making ice less dense than water
  • this allows the top layer of water to freeze and stay afloat while aquatic life continues underneath
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

why are hydrogen bonds important in DNA

A

hold together the bases in DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

define dispersion forces

A

weak electrostatic interactions between nonpolar compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what makes dispersion forces stronger

A
  • larger polarizability
  • larger atoms: strength increases with molecular weight
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the strongest intermolecular force that can exist between nonpolar molecules

A

dispersion forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the order of strength of intermolecular forces

A
  • weakest: dispersion
  • middle weakest: dipole-dipole
  • strongest: ion-dipole and hydrogen bonds
20
Q

what is the order of strength of intramolecular forces

A
  • weakest: covalent bonds
  • strongest: ionic bonds
21
Q

which are stronger: intermolecular forces or intramolecular forces

A

intramolecular forces (within molecules)

22
Q

describe the movement of particles in the gas phase

A

complete freedom of motion

23
Q

describe the movement of particles in the liquid phase

A

free to move relative to each other

24
Q

describe the movement of particles in the solid phase

A

particles in essentially foxed positions

25
Q

do boiling points and melting points vary with pressure

A
  • yes
  • can be seen in a phase diagram
26
Q

describe a phase diagram

A

shows the boiling and melting points of a substance based on temperature and pressure

27
Q

at what pressure are the normal melting and boiling points of a substance

A

1 atm

28
Q

define sublimation and deposition

A
  • sublimation: transition of substance from solid state to gas state
  • deposition: transition of substance from gas state to solid state
29
Q

what is an example of a substance that undergoes sublimation and depostion

A

dry ice

30
Q

what is the triple point in a phase diagram

A

the temperature and pressure where all 3 phases are in equillibrium

31
Q

what is the critical point in a phase diagram

A

the temperature and pressure where you cannot distinguish between the liquid and gas phase

32
Q

describe how the phase diagram of water differs from the phase diagrams of most other substances

A
  • water: the line between the solid and liquid phase leans left
  • other: the line between the solid and liquid phase leans right
33
Q

what happens if you squeeze ice at a contsant temperature

A

it melts

34
Q

why is the fact that the line between the solid and liquid phases in the phase diagram for water significant

A

explains why the liquid phase of water is more dense than the solid phase

35
Q

in which phase of water are hydrogen bonds more stable

A
  • more stable in ice
  • less stable (constantly break and reform) in liquid
36
Q

define vapor pressure

A

the pressure of molecules that evaporate all the time in any sample of liquid

37
Q

describe the vapor pressure of volatile liquids

A
  • vapor pressure is high
  • causes the liquid to evaporate quickly
38
Q

in which temperature range (high or low) do a higher proportion of molecules have the minimum kinetic energy needed to escape the liquid phase

A

higher temperature range

39
Q

does vapor pressure vary with temperature

A

yes

40
Q

do stronger or weaker intermolecular forces result in higher vapor pressure and why

A
  • weaker intermolecular forces
  • less force/energy required to break forces and get molecules into gas phase
41
Q

why is the vapor pressure in volatile liquids high and how does this affect the boiling point

A
  • molecules are experiencing weaker intermolecular forces
  • have lower boiling points
42
Q

what is the boiling point in terms of Pvap and Patm

A

the temperature where Pvap = Patm

43
Q

do polar or nonpolar substances have a higher vapor pressure and why

A
  • nonpolar
  • nonpolar substances have weaker intermolecular forces (dispersion forces); easier for intermolecular forces to break which results in higher vapor pressure (meaning they are more volatile); also have a lower boiling point
44
Q

do volatile liquids have a higher or lower boiling point than non-volatile liquids

A

lower

45
Q

do compounds with stronger dispersion forces (larger) have higher or lower boiling points

A

higher boiling point

46
Q

how do the boiling points of liquids at high altitudes (low pressure) compare to those at lower altitudes (high pressure)

A

lower boiling points at high altitudes

47
Q

should you boil pasta for a longer or shorter amount of time at higher altitudes (low pressure)

A

longer time

CHEM 119 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions