Quiz tomorrow: Chapter 11'3 Molecular Orbital Theory

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Quiz tomorrow Chapter 11.3 (Molecular Orbital
Theory) Chapter 15 (Section 15.4
Do not need to know detailed reactions)
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Section 15.3 Organic Reaction Types
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Show why is this reaction energetically favorable
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Section 15.3 Organic Reaction Types
2) Elimination reactions opposite of addition
reactions saturated reactant ? saturated product

Example
Generic reaction
Characteristics Typically eliminates 2
halogens (i.e. Cl2), H and halogen (i.e. HBr), or
H and OH group (i.e. H2O) Driving force of
this reaction is formation of small, stable
molecules
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Thermodynamics in a Nutshell
G Gibbs free energy in chemistry, the force
that causes chemical reactions
can tell us whether or not a reaction will occur
H enthalpy keeps track of the quantity of
energy in chemical reactions, it is
the energy change during a reaction
(?Hreaction, ?Hlattice) You can ask Will
the reaction occur spontaneously? ?H is
negative ? exothermic (energy loss as heat)
more stable YES ?H is positive ?
endothermic (energy needs to be added) less
stable NO
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Thermodynamics in a Nutshell
G Gibbs free energy in chemistry, the force
that causes chemical reactions
can tell us whether or not a reaction will occur
S entropy keeps track of the distribution of
energy in a system energy becomes
distributed more uniformly (more disorder) with
time
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Summary Thermodynamics in a Nutshell
G Gibbs free energy in chemistry, the force
that causes chemical reactions
can tell us whether or not a reaction will occur
H enthalpy keeps track of the quantity of
energy in chemical reactions, it is
the energy change during a reaction
(?Hreaction, ?Hlattice) You can ask Will
the reaction occur spontaneously? ?H is
negative ? exothermic (energy loss as heat)
more stable YES ?H is positive ?
endothermic (energy needs to be added) less
stable NO
S entropy keeps track of the distribution of
energy in a system energy becomes
distributed more uniformly (more disorder) with
time
You can ask Will the reaction occur
spontaneously? uniformity/disorder
increases ? YES uniformity/disorder
decreases ? NO
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Section 15.3 Organic Reaction Types
3) Substitution reactions
Generic reaction
Example
Characteristics C involved in bonding can be
saturated or unsaturated (involved in double,
triple bonds)
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Section 15.3 Redox Process in Organic Reactions
Oxidation-reduction reactions in O-chem Do
NOT monitor change in O.N. of various C atoms in
a compound. Rather, note movement of e-
density around C based on of more/less EN atoms
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Section 15.4 Properties Reactivities of
Functional Groups
The distribution of e- density in the functional
group affects the reactivity

• Functional groups with single bonds only
• alcohols, haloalkanes, amines

(2) Functional groups with double bonds
alkenes, carbonyl group (aldehydes ketones)
(3) Functional groups with both single and double
bonds carboxylic acid, ester, amide
(4) Functional groups with triple bonds
nitrile, alkynes
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Section 15.5 Monomers Polymers Synthetic
Macromolecules
Polymers many monomer units bonded together
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Section 15.5 Monomers Polymers Synthetic
Macromolecules
Petroleum-based products there will be a
shortage of raw materials soon
bisphenol A (BPA)
- used in synthesizing DGEBA, a building block
for an epoxy resin
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Section 15.5 Monomers Polymers Synthetic
Macromolecules
Addition polymers as each monomer adds to the
chain, it forms a new reactive site.
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Section 15.6 Monomers Polymers Biological
Macromolecules
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Section 15.6 Polysaccharides
Glucose is a monosaccharide alcohol and
aldehyde groups react to make cyclic
forms Polysaccharide chains formed from cyclic
forms that undergo dehydration reactions.
Different disaccharides formed from different
monosaccharides sucrose (table sugar) glucose
(C-1) fructose (C-2) lactose (milk sugar)
glucose (C-1) galactose (C-4) maltose (beer)
glucose (C-1) glucose (C-4)
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Section 15.6 Polysaccharides
3 main groups of polysaccharides Cellulose
most abundant organic chemical on earth,
structural function (plant cell walls),
long chains of glucose, humans cannot digest this
(cows, sheep, termites) Starch energy
storage in plants (amylose and amylopectin)
Glycogen energy storage in animals
(C6H10O5)n
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Section 15.6 Amino Acids and Proteins
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Section 15.6 Amino Acids and Proteins
hydrophobic interactions between CH3
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Section 15.6 Nucleic Acids, DNA, and RNA
Pyrimidines Thymine (T) Uracil (U), cytosine
(C) Purines Guanine (G), Adenine (A) A T(U)
, G C