AP Chemistry Chapter 13 Notes
(Student Edition)
Chapter 13 problem set:3, 5, 7, 12, 19, 22, 23, 25, 26, 40, 42, 48-50, 52, 53, 57, 59, 67, 70, 71, 73, 76, 78, 84, 88, 89, 109, 129
Figures/tables/charts/pictures are really important to look at in this chapter.
Read the Enrichment (Clausius-Clapeyron Equation) p. 495
Sections 13.10-13.14 It is strongly suggested that you make notes on the sections and attempt some of these problems.
13-1 Kinetic-Molecular Description of Liquids and Solids
Read this section. In liquids and solids ( states), the particles are together and interact with each other to a , so they behave differently than .
__P__T__P__T
Changing Phase:Gas Liquid Solid
Learn characteristics of each phase (Table 13-1) and learn diagrams (Figure 13-1)
13-2 Intermolecular Attractions and Phase Changes
Intramolecular force (aka ) – – for water 250 kcal
Intermolecular force () – , but not near bond strength – 10 kcal (H2O)
So….H2O(l) H2O(g) not…. H2O(l) H2(g) + O2(g)
States of matter are a function of
Types of IMF:
a) ion-ion interaction – found in ionic solids
F (q+)(q-)as…q F__ and as… d F __
d2
melting points: NaCl 801 Co BaS 1200 Co MgS 2000 Co CaO 2580 Co
Draw NaCl:
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b) dipole-dipole interaction
draw HCl dipoles, electronegativity differences, etc.
F 1/d4 - only effective at distances
About of ion-ion interactions
IMF depends on geometry – examples:
Molecule “A” / Molecule “B” / Shape “A” / Shape “B” / Symmetry “A” / Symmetry “B” / Polarity “A” / Polarity “B” / Stronger IMFCO2 / SO2
BCl3 / ICl3
XeCl4 / SCl4
c) Hydrogen Bonding – “super” dipole-dipole
2 conditions 1. H must be bonded to 2. Other molecule must have
will C2H6O have hydrogen bonds? ….Draw below:
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Does CH2O have H-bonds? …..Will CH2O H-bond with water?
d) London Forces (Dispersion Forces)
Temporary dipoles caused by the motion of .
One atoms nucleus is attracted to the electron clouds of another atom.
Larger forces in larger . Check out the states of matter in the Halogen family
F 1/d7 - effective only at
Molecule / Shape / Symmetry / H having FON? / Polarity / IMFNH3 / Pyramidal / Asymmetrical / Yes / Polar / Hydrogen Bonding
ClF
H2
He
CO
CO2
XeF4
ClBr3
XeF2
HCN
Arrange H2S, H2O, CH4, H2, KBr in order of increasing attractive forces: ______
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13-3 Viscosity
Resistance to . Proportional to .
Honey – viscosityGasoline – viscosity
C8H18 – viscosityC12H26 – viscosity
Glycerin – three carbon chain with three hydroxyl groups (draw):
highly due to multiple sites.
Relationships: attractive forces=__ viscosity
temperature=__ viscosity
Viscosity is measured with an Ostwald viscometer – measures time it takes for liquid to flow
through a small neck of known size.
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13-4Surface Tension
The invisible “skin” on the of a liquid.
Molecules below the surface of a liquid are affected by .
Molecules on the surface are attracted towards the .
These inward forces, if strong, tend to make the molecules form .
Examples are blood drops, beads of water on a freshly waxed car, shapes of soap bubbles.
Surface tension also supports water striders.
13-5Capillary Action
With liquids, two forces greatly affect behavior – .
Cohesive forces = forces holding together.
Adhesive forces = forces between the .
Why is a meniscus in a graduated cylinder concave with water/convex with Hg?
Why does water rise up tree roots? Why does water “wet” glass?
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13-6Evaporation
Process by which high energy molecules escape from the .
Graph showing distribution of molecules at lower/higher temperatures.
(Fraction of molecules vs. kinetic energy)
Closed vs. open container:
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13-7Vapor Pressure
The partial pressure of vapor molecules above the of a liquid at at a given
.
Manometer open and closed:
As IMF increases, VP . As T increases, VP .
Comparision of vapor pressure vs. temperature:
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Graph of Vapor PressureVs. Temperature:
13-8Boiling Points and Distillation
If VP increases with temperature, it will eventually = atmospheric pressure. This is when
occurs. Boiling can also happen by reducing atmospheric pressure.
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Boiling Point and Elevation:
So, as elevation increases, atmospheric pressure and boiling point . A pressure cooker the pressure inside the cooking vessel. This causes the boiling point to . Thus, food will cook at a temperature and .
Distillation apparatus (separation of components in a mixture based on differences):
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13-9Heat Transfer Involving Liquids – We’ve done this before…
Heating curve/cooling curve:
Heat Diagram for Water:
As energy increases, temperature . Therate of increase (slope) depends on specific
heat of material. Equation for these sections is q =
The flat areas show as energy increases, temperature . The energy in these
sections all go into changing . Equation for these sections is q =
Note that the H can be H or H
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Example: How much heat is required (in calories) to transform 50.0 g of ice
at - 10.0 °C to steam at 110.0 °C?
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Other Examples to do on your own….answers are given below:
Example:How much heat is needed to heat 100.0 grams of ice at -10.0 oC to steam at 110.0 oC?
2030, 33400, 41800, 226000, 2030 = 305320 J
Example: How much heat is needed to heat 100.0 grams of ethyl alcohol at -10 oC to 110.0 oC?
21700, 85800, 3020 = 110520 J
Example: How much heat is released as 2.0 moles of C6H6 is cooled from 100.0 oC to 60.0 oC?
3264, 78600,5440 = 87000 J
Example: Explain why 100.0 g of steam at 100 oC would burn you more than 100.0 g of water at
the same temperature as both samples hit your skin and cool to skin temperature of
33.0 oC.
Additional 226,000 J absorbed by skin as water gas turns into water liquid
Students take their own notes on the following sections:
13-10 Melting Point
13-11 Heat Tranfer Involving Solids
13-12 Sublimation and Vapor Pressure of Solids
13-13 Phase Diagrams
13-14 Amorphous vs. Crystalline Solids
13-15Structures of Crystals
Crystals are composed of repeating .
These cells are described by sides (a,b,c) and angles (α,β,γ)
There are many types of cells – cubic tetragonal, orthorhombic, etc. (don’t need to memorize)
Crystal problems - show simple cubic, face centered cubic, body center cubic
- show number of atoms per unit cell
- some basic math formulas here (for volume, for triangle sides)
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Example: A metal crystallizes in a face centered cubic crystal with a unit cell edge length of 4.38 Angstroms. Calculate atomic radius, volume of one atom in cubic Angstroms and cm3, and density of the metal. (Atomic weight = 209 g/mole)
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13-16Bonding in Solids
Crystalline solids are classified by the type of of which they are composed and their
______.
Type / Particle / Force / ExampleIonic
Covalent
Molecular
Metallic
Ionic solids – hard, brittle, poor conductors as solids, but good if melted, high mp
Covalent solids (Network solids) – very hard, poor conductors, high mp, column IV A
Molecular – soft, poor conductors, low to moderately high mp
Metallic – sea of electrons theory – malleable, ductile, sectile, good conductors
13-17Band Theory of Metals – not covered in this course
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