1. Unit 12
Chapters 11, 12, 13, 25

2. Organic Molecules Hydrocarbons
Compounds containing only carbon and hydrogen
Carbon always makes 4 bonds
N – 3, O – 2, H – 1
Alkanes are all single bonds
Alkenes have a double bond
Alkynes have a triple bond

3. Condensed Structural Formula
Shows who is bonded to who, without the actual bonds
H H H
│ │ │
H─ C─ C─ C─ H
H H H
│ │ │
H─ C─ C= C─ H │ H

4. Functional Groups
Specific arrangement of atoms that give compounds a unique property
Usually involve more than C, H’s
Can be on the end of a chain, in the middle, or separating chains

5. Organic Molecules Halides or halocarbons Alcohols Amine
Halogen attached to a carbon
Alcohols
–OH group attached to Carbon (–O–H)
Amine
Nitrogen attached to a carbon (–NH2)

6. Organic Molecules O ǁ ─ C ─ H Aldehyde Carbonyl group at end of chain
Name ends with –al
Condensed structural formula ends with -CHO
H H O
│ │ ǁ
H─ C─ C─ C─ H
│ │
H H
H H H H O
│ │ │ │ ǁ
H ─ C─ C─ C─ C─ C─ H
│ │ │ │
H H H H
Propanal
Pentanal
CH3CH2CHO
CH3CH2CH2CH2CHO

7. Organic Molecules O ǁ ─ C ─ O ─ H Organic acid
Carboxyl group on end of chain
Name ends in –oic acid
Condensed structural formula ends with -COOH
Hydroxyl H is the acidic H
H O
│ ǁ
H ─ C─ C─ OH │ H
Ethanoic Acid
CH3COOH

8. Organic Molecules O H ǁ ǀ ─ C ─ N ─ H Amide
ǁ ǀ
─ C ─ N ─ H
Amide
Carbonyl group with an amine group attached to it
Must be on an end
Name ends in -amide
H H O
│ │ ǁ
H─ C─ C─ C─ NH2
│ │
H H
Propanamide
CH3CH2CONH2

9. Organic Molecules Ketone Ether Double bonded oxygen on a middle carbon
Name ends with –one
Ether
Single oxygen between 2 carbon chains
H O H
│ ǁ │
H─ C─ C─ C─ H
│ │
H H
Acetone
CH3COCH3
H H H H
│ │ │ │
H─ C─ C─O ─ C─ C─ H
Diethyl Ether
CH3CH2OCH2CH3

10. Organic Molecules O ǁ ─ C ─ O ─ Ester
Carbonyl group with single oxygen between carbon chains
Named in two parts
1st Branch off oxygen first as alkyl group
2nd Chain containing Carbonyl group
Ending in –oate
H O H
│ ǁ │
H ─ C─ O ─ C─ C─ H
│ │
H H
Methyl Ethanoate
CH3COOCH3

11. Isomers
Two or more compounds with the same chemical formulas, but different structural formulas and different properties
Different Names
H H H H H
│ │ │ │ │
H ─ C─ C─ C─ C─ C─ H
H H CH3 H
│ │ │ │
H─ C─ C─ C─ C─ H
H H H H
C5H12
H CH3 H
│ │ │
H─ C─ C─ C─ H
Pentane
Methyl Butane
2,2-Dimethyl Propane

13. States of Matter
The main difference between the states of matter is difference in distance between particles
Condensed phases
Solids, liquids
Fluids
Liquids, gases

14. States of Matter The state of a substance depends on two main factors
Kinetic energy of particles
Attraction between particles
Intermolecular forces of attraction

15. Intermolecular Forces
Three main forces
Dispersion
nonpolar
Dipole-dipole
polar
Hydrogen bonds
H with N, O, F

16. Dispersion Forces
Attraction between electrons of one atom and protons of another atom
Induced dipole
All atoms and molecules have dispersion forces

17. Dispersion Forces

18. Dispersion Forces
Attractive forces increase with increasing number of electrons
more polarizability
Attractive forces increase with increasing mass

19. Dispersion Forces
More surface areas increases attraction

20. Dipole - Dipole Attraction between polar molecules
This is in addition to dispersion forces

21. Dipole - Dipole

22. Hydrogen Bonds
A hydrogen bonded to an N, O, F will be attracted to another N, O, F
N, O, F are both very small and very electronegative
Special case of dipole – dipole
HF, NH3, H2O….

23. Hydrogen Bonds

24. Intermolecular Forces
Ion – Dipole
Regents: Molecule Ion
Ionic compounds dissolved in polar solvents
Discussed later in unit with solutions

26. Solids State of matter with a definite volume and definite shape
Particles are packed tightly together
Two types
Crystalline
Amorphous
Non-crystalline

27. Crystalline Solids
Particles are in a highly ordered arrangement

28. Amorphous Solids
No particular order to the arrangement

29. Network Covalent Solids
All atoms are connected in a network of covalent bonds
Diamonds, graphite, SiO2
Very hard
Very high melting and boiling points
Usually not conductive

30. Network Covalent Solids

31. Solids Type Bond Type MP, BP Conductivity Soluble in H2O Molecular
Covalent
Low No
Polar only
Network
Very High
Ionic
High
Liquid, Dissolved
Most
Metallic
Solid, Liquid

32. Semiconductors
Material with electrical conductivity between a metal and an insulator
Metal > semiconductor > insulator
Usually C, Si, Ge

33. Semiconductors Doping Addition of impurities p-type n-type
One less valence electron (positive) Ga
n-type
One extra valence electron (negative) As

35. Liquids
State of matter with a definite volume, but takes the shape of its container.
Particles are close to each other due to intermolecular forces
Particles are able to slide past each other due to kinetic energy

36. Liquids
Intermolecular forces play a large role in determining a number of properties of liquids
Surface Tension
Viscosity
Capillary Action
Vapor Pressure

37. Surface Tension Tendency of a liquid to minimize surface area
Stronger intermolecular forces cause higher surface tensions

38. Viscosity Resistance of a liquid to flow
Stronger intermolecular forces cause higher viscosity

39. Affect of Temperature Increasing temperature decreases surface tension
Increasing temperature decreases viscosity
Decreasing surface area also decreases viscosity

40. Capillary Action
Ability of a liquid to flow up a thin tube against the pull of gravity

41. Capillary Action Happens because of two forces working together
Cohesion
Force that holds liquid molecules together
Adhesion
Attraction of liquid molecules to container walls

42. Meniscus Curving of a liquid surface in a thin tube Water Mercury
Adhesion > Cohesion
Mercury
Cohesion > Adhesion

43. Vapor Pressure Pressure exerted by a vapor in equilibrium with liquid
Stronger intermolecular forces cause lower vapor pressure
More attraction = less evaporation

45. Solution Homogeneous Mixture Components can’t be filtered
Uniform Throughout
Components can’t be filtered
Particles aren’t large enough to scatter light
Tyndall Effect

46. Separating Mixtures Evaporation – evaporate away liquid to leave solid
Distillation – Separates homogeneous liquid mixtures based on different boiling points
Chromatography – separation of substances based on polarity and intermolecular forces

47. Solution Components Solvent Solute Dissolving medium in mixture
Usually water
Solute
Dissolved particles in solution
Solute goes into solvent

48. Molarity Molarity = Moles of Solute Liters of Solution 1 mol/L = 1 M
Often used for solids dissolved into liquids
Most common concentration system

49. Solubility Soluble Insoluble Solute will dissolve in solvent
Solute will not dissolve in solvent

50. Solubility Miscible Immiscible Soluble liquid – liquid mixtures
Ammonia is miscible in water
Immiscible
Insoluble liquids
Oil is immiscible in water

51. “Like Dissolves Like”
Polar and ionic substances will dissolve in polar solvents
Nonpolar substances will dissolve in nonpolar solvents

52. “Like Dissolves Like”
Acetone is soluble in water because of dipole – dipole interactions
Iodine will dissolve in hexane because of dispersion interactions

53. “Like Dissolves Like”
NaCl will dissolve in water because of Ion – Dipole interactions
Polar ends of water will be attracted to oppositely charged ions of ionic compounds
Solvation

54. Coulomb’s Law
There are stronger ion – dipole interactions when ionic charges are larger
Ca2+ > Na+
There are stronger ion – dipole interactions when ions are smaller
Li+ > Na+

56. Spectrophotometry Using light to make measurements in chemistry
UV – electronic transitions
Visible – solution concentration
Infrared – molecular vibration
Microwave – molecular rotation

57. Spectrophotometry Devices
Spectrophotometer
Measures transmittance over a range of wavelengths
Colorimeter
Measures absorbance of specific wavelengths

58. Spectrophotometry Devices
Spectrophotometer

59. Spectrophotometry Devices
Colorimeter

60. Beer’s Law Relates the absorbance of light to concentration A = abc
A = Absorbance
a = molar absorptivity (unique to substance)
b = path length
c = concentration

61. Beer’s Law
Calibration curve