Chapter 11 Notes Flashcards
1
Q
What is matter?
A
anything that occupies spaces and has mass
2
Q
What are the 4 phases of matter? What’s another name for them
A
Solids, Liquids, Gasses, and Plasma
Common Phase States
3
Q
What are the molecular properties of solids?
A
- hard, rigid
- molecules touch each other
- vibrate in fixed positions
- do not move around each other
4
Q
What are the molecular properties of liquids?
A
- in constant motion
- moves freely about each other(they slide past each other)
- more tightly packed than gasses
- compressible
5
Q
What are the molecular properties of gasses?
A
- very spaced out from each other
- don’t often touch each other
- very random motion
- compressible
6
Q
What is Fluidity?
A
the ability of something to flow
7
Q
Name the Phase Changes
A
Solid -> Liquid: melting(fusion) Solid-> Gas: sublimation Liquid -> Solid: freezing Liquid-> Gas: evaporation(vaporization) Gas-> Solid: deposition Gas-> Liquid: condensation
8
Q
What are Intermolecular Forces (IMFs)?
A
forces of attraction between molecules that hold them together in condensed states
9
Q
What are the 4 types of IMFs?
A
Dispersion
Dipole-Dipole
Ion-Dipole
Hydrogen Bonds
10
Q
What are Dispersion Forces?
A
- weak attractive force between 2 molecules due to a temporary shift in electron density
- it is the weakest type of IMF and occurs in all matter
11
Q
What are Dipole-Dipole Forces?
A
- forces between 2 polar molecules; caused by the tendency of dipoles to line up with the positive end of 1 molecule near the negative end of another
- stronger force than Dispersion with permanent dipoles in the molecules
12
Q
What are Ion-Dipole Forces?
A
- forces of attraction between a dipole and anion
- 2nd Strongest type of IMF
13
Q
What are Hydrogen bonds?
A
- forces that exist between a hydrogen atom attracted to a more electronegative atom (F,O,N) inside a molecule
- STRONGEST type of IMFs
14
Q
What are Factors that affect Dispersion Forces
A
- Molar Mass- with similar compounds; the greater the molar mass, the greater the depression force and the boiling point will be higher
- Molecular shape- with the same molecular formula, a linear structure has a higher boiling point than those that are branched or round in structure
15
Q
What is surface tension?
A
- the tendency of liquids to minimize their surface area
- it is also the energy required to increase the surface area by a unit amount
16
Q
What is water’s surface tension at room temperature?
A
72.8 mJ/m^2
17
Q
How does surface tension relate to IMF?
A
surface tension decreases as IMFs decreases
18
Q
What is Viscosity?
A
the resistance of a liquid to flow
ex: honey, molasses, motor oil
19
Q
How is viscosity measured?
A
it’s measured in poise (P) or (cP)
1 poise= 1g/ cm*s
20
Q
How is viscosity related to IMFs?
A
viscosity increases as IMFs increases and also depend on the molecular shape
21
Q
How does viscosity relate to temperature?
A
As temp increase, viscosity decreases (in vice versa)
22
Q
What is Capillary Action?
A
the ability of a liquid to flow against gravity up a narrow tube
23
Q
How does Capillary Action work?
A
The liquid is more attracted to the glass of a tube than it is to itself. This is because the adhesive forces, the force between 2 different types of molecules, are greater than cohesive, force between like molecules, of the liquid in question
24
Q
What is Vapor Pressure?
A
partial pressure of a vapor over its liquid at equilibrium
25
How does Vapor Pressure occur?
Vapor pressure is due to the evaporation of molecules from the surface of the liquid
26
What are Volatile and Nonvolatile liquids?
Volatile Liquids: liquids that are easily vaporized
| Nonvolatile Liquids: liquids that aren't easily vaporized
27
What is Dynamic Equilibrium?
a state of balance in which 2 opposing processes are occurring at equal rates
28
How are gasses volatile?
Gasses can be liquefied by decreasing temp and increasing pressure
29
What is Vaporization/Boiling?
going from a liquid phase to a gaseous phase
30
Boiling point
temp at which vapor pressure and atmospheric pressure are equal
31
Normal Boiling point
boiling point at 1 atm of pressure
32
Melting point
temp at which a crystalline solid melts
33
Freezing point
temp at which liquid changes to a crystalline solid
34
What is Heat of Vaporization (∆Hvap)?
the amount of heat required to vaporize 1 mol or 1 gram of a liquid at its boiling point
p.s. it will always be a positive value
35
What's another name for ∆Hvap?
Enthalpy
36
what is the ∆Hvap of vaporizing water? Condensing water?
```
Vaporizing water (L -> G): 40.7 kJ/mol
Condensation (G -> L): -40.7 kJ/mol
```
37
When is pressure endothermic?
When ∆Hvap is positive, because heat is absorbed from the surroundings
38
When is pressure exothermic?
When ∆Hvap is negative, heat is released into the surroundings
39
What is the Clausius-Clapeyron equation (that is needed for the test)?
The two-point method: ln (P1 / P2) = (-ΔH / R) (1/T2 - 1/T1)
40
What is R (the constant) in the Clausius-Clapeyron equation?
R= 8.314 J/molK
41
What is the Critical Point?
the point at which a liquid is not distinguishable from a gas
42
What is sublimation?
the transition from solid to gas
43
What is deposition?
the transition from gas to solid
44
What's fusion?
the transition from solid to liquid
45
What's freezing?
the transition from liquid to solid
46
What is the heat of fusion (ΔHfus)?
the amount of heat required to melt 1 gram or 1 mole of a solid
47
ΔHfus of water
6.02 kJ/mol; it's endothermic
48
ΔHfreezing of water
-6.02 kJ/mol: it's exothermic
49
What's a Phase Diagram?
A map of the state of a substance depending on the temp. and pressure
y-axis: displays pressure (Torr)
x-axis: displays temperature (Celcius)
50
What's a Crystalline Lattice?
the regular arrangement of atoms in a crystalline solid (frozen solid)
51
What's a Unit Cell?
the smallest divisible unit of a crystal that, when repeated in 3D, reproduces the entire crystal lattice
52
What's a Simple Cubic Unit Cell?
a unit cell that consists of a cube with one atom at each corner
53
What's a body-centered cubic unit cell?
A unit cell that consists of a cube with 1 atom at each corner and 1 atom (of the same kind) in the very center of the cube
54
What's a face-centered cubic unit cell?
a cube with one atom at each corner and one atom (of the same kind) in the center of each cube face
55
What are the types of molecules?
Molecular solids: solids whose composite units are molecules. Ex: H20
Ionic solids: solids whose composite units are ionic Ex: CaF2
Atomic: solids whose composite units are atoms Ex: Xe, Fe, SiO2
56
What are the different types of atomic solids?
Nonbonding atomic solids: held together by relatively weak dispersion forces
Metallic atomic solids: held together by metallic bonds which are represented by the interactions of metal cations
Network covalent atomic solids: held together by covalent bonds, the crystal structures of theses solids are more restricted by the geometrical constraints of the covalent bonds
57
What's a solution?
homogenous mixture of two or more substances or components
58
What are the two main parts of a solution?
solutes: minor components; usually what is being dissolved
solvent: major components; usually what does the dissolving
59
What is Miscibility?
ability to mix
60
What is Solubility?
measure of how soluble a substance is
61
What is Entropy?
the tendency of a solution to mix; measure of energy randomization or energy dispersal in a system
62
IMFs exists between...
1. solvent- solute particles
2. solvent particles
3. solute particles
63
What is the rule of thumb for distinguishing between polar and nonpolar molecules?
Like mixes with like:
Polar mixes with polar
Nonpolar mixes with polar
64
Saturated Solution
a dissolved solute is in dynamic equilibrium with the undissolved solute; any additional solute will not dissolve
65
Unsaturated solution
solution that contains less that the dynamic equilibrium amount of solute; any additional solute will dissolve
66
Supersaturated solution
solution that contains more than the equilibrium amount of a solute
67
What are the Factors that Affect Solubility
Temperature: solubility of most solids in water increases with increasing temp
Pressure: solubility of gasses in liquids decreases with increasing temp
68
What is pressure?
solubility of gasses in liquids increases with increasing pressure
69
What are the ways to measure solution concentration?
```
Molarity (M)
Molality (m)
Parts by Mass (% Mass)
Parts by Volume (ppm/ppb)
Mole Fraction
Mole Percentage
```
70
What is Molarity (M)?
- moles of solute/liter of solution
- this depends on volume
- varies with temperature
71
What is Molality (m)?
mol of solute/ kg of solvent
72
What is Parts by Mass?
ratio of the mass of solute to the mass of solution times 100; mass of solute/mass of solution time 100
73
What are the two variants of Parts by Volume?
parts by million(ppm): mass of solute/ mass of solution times 10^6
parts by billion (ppb): mass of solute/mass of solution time 10^9
74
What is a Mole Fraction?
Xsolute= nsolute/nsolute + nsolvent
75
What is Mole Percentage?
Xsolute times 100
76
What is Colligative Properties?
properties that depends on the number of dissolved particles in a solution
77
What are the 4 types of Colligative Properties
Vapor Pressure Lowering
Freezing Point Depression
Boiling Point Elevation
Osmotic Pressure
78
Raoult's Law (used to find vapor pressure)
the vapor pressure of an ideal solution is dependent on the vapor pressure of each component and the mole fraction of the component in the solution
79
Ideal solution
both the solvent and solute contribute to the overall vapor pressre of the solution
80
The Interactions between the solvent-solute particles...
are in equal magnitude that distinguishing between solute-solvent is not needed
81
What's the Freezing Point Depression?
Freezing Point of a pure solvent has been reduced by the addition of a solute
82
What is the Van't Hoff Constant?
number of moles of particles/ moles of formula units dissoved
