Chemistry 121(001) Winter 2015
Introduction to Organic Chemistry and Biochemistry
Instructor Dr. Upali Siriwardane (Ph.D. Ohio State)
E-mail: upali@latech.edu
Office: 311 Carson Taylor Hall ; Phone: 318-257-4941;
Office Hours: MTW 8:00 - 10:00 am;
ThF 9:00 - 10:00 am 1:00 - 2:00 pm.
December 19, 2014: Test 1 (Chapters 12-13)
January 26 , 2015: Test 2 (Chapters 14-16)
February 13, 2015: Test 3 (Chapters 17-19)
March 2, 2015:
Test 4 (Chapters 20-22)
March 3 , 2015: Make Up Exam: Chapters 12-22)
Bring Scantron Sheet 882-E
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Slides & GHW Questions
GHW#1
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Chapter 12. Saturated Hydrocarbons
12.1 Organic and Inorganic Compounds, 341
12.2 Bonding Characteristics of the Carbon Atom, 342
12.3 Hydrocarbons and Hydrocarbon Derivatives, 342
12.4 Alkanes: Acyclic Saturated Hydrocarbons, 343
12.5 Structural Formulas, 344
12.6 Alkane Isomerism, 346
12.7 Conformations of Alkanes, 348
12.8 IUPAC Nomenclature for Alkanes, 350
12.9 Line-Angle Structural Formulas for Alkanes, 356
12.10 Classification of Carbon Atoms, 358
12.11 Branched-Chain Alkyl Groups, 359
12.12 Cycloalkanes, 361
12.13 IUPAC Nomenclature for Cycloalkanes, 362
12.14 Isomerism in Cycloalkanes, 363
12.15 Sources of Alkanes and Cycloalkanes, 365
12.16 Physical Properties of Alkanes and Cycloalkanes, 367
12.17 Chemical Properties of Alkanes and Cycloalkanes, 368
12.18 Halogenated Alkanes and Cycloalkanes, 371
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1. Circle the correct compound type (ionic or
covalent) for the
following:
formula
compound type
a) NBr3
(ionic or covalent)
b) NaCl
(ionic or covalent)
c) C2H5OH
(inorganic or organic)
d) NH4NO3
(inorganic or organic)
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Shapes of Atomic Orbitals
– A s orbital consists of sphere with the center at
the nucleus
– A p orbital consists of two lobes arranged in a
straight line with the center at the nucleus
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Shapes of p Atomic Orbitals
– A p orbital consists of two lobes arranged in a
straight line with the center at the nucleus
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Hybridizations of Atomic Orbitals
– sp3 tetrahedral 109.5
– sp2 trigonal planar 120
– sp linear 180
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Electronic Configuration of atoms
Ground state electronic configuration of atoms in core format
Carbon (C):
[He] 2s2, 2p2
or [He] 2s2, 2px13py13pz0
Potassium (K):
[Ar] 4s1
Phosphorous (P):
[Ne] 3s2, 3p3
Valence shell electronic configuration
Carbon (C):
3s2, 3p2
Potassium (K):
4s1
Phosphorous (P):
3s2, 3p3
How you get the electronic configuration of an atom from the periodic
table?
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2.For the atoms and ions below, circle the
correct ground state valence electron
configuration of carbon in core format:
a) Carbon (C): 2s1, 2px12py12pz1
b) Carbon (C):
4s1 or 3s2, 3p6
c) Carbon (C): [Ne] 3s2, 3p3
d) Carbon (C):
[He] 2s2, 2px12py12pz0
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Lewis structure of atoms (Review)
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Slide - 10
3. Circle the Lewis structures of the following atoms:
a) N
b) C
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Drawing Lewis structure molecules and ions (Review)
1) Add all valence electron of atoms in the molecule from the formula.
2) Add the ion charge for negative ions or subtract for positive ions.
3) Draw the skeletal structure by connecting the atoms with single
bonds.
4) Give each of the atoms an octet (8 e-). Adding unshared pairs of
electrons
5) Count the total number of e- used through step 4 and compare to
the number calculated in
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4. Circle the correct Lewis structure for following compounds:
a) CH3OH
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Electronegativities of Elements
Electronegativity
The ability of one atom in
a molecule to
attract electrons to itself.
H-O-H
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Classify following bonds nonpolar-covalent,
polar-covalent or ionic bonds
N-H
3.0 and 2.1 = 0.9
O-H
3.5 and 2.1 = 1.4
C-H
2.5 and 2.1 = 0.4
C-F
2.5 and 4.0 = 1.5
Na-Cl 0.9 and 3.0 = 2.1
Al-Cl 1.5 and 3.0 = 1.5
Pure Covalent: 0-0.4
Polar Covalent: 0.5-1.5
Ionic Bond:
<1.5
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5. Circle the most polar bond in the
following molecule
:
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Classifying
Organic Compounds
(hydrocarbon derivatives)
Examples
Functional Group Ending
Hydrocarbons C and H only
Alcohols
R-OH
Haloalkanes
R-Cl
Ethers
R-O-R’
Acids
R-COOH
Amines
R-NH2
Ketones
R(C=O)R’
Aldehydes
R-CHO
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-ane
-ol
-halide(chloride)
-ether
-oic acid
-amine
-one
-al
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Types of formula for organic compounds
Chemical formula: Indicate the kind and number of each type of
atom in the molecule.
Condensed formula: Shows skeletal atoms in a molecule and
places them in a sequential order that indicates bonding.
Condensed Structural formula: Shows each atom and bonds in a
molecule.
Expanded Structural formula: Shows each atom and bonds in a
molecule.
Line-angle formula: The hydrogen atoms are removed from
carbon chains, leaving just a carbon line skeleton with functional
groups attached to it.
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Acyclic Alkanes
Are saturated hydrocarbons:
Noncyclic alkanes: General molecular formula, CnH2n+2
Structural formula:
•Normal alkanes n-alkane
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6. Name the functional group in each of
the following molecules
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7) Give the formulas for each of the
following:
a)
i)
Molecular formula:
ii) Condensed formula:
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7) Give the formulas for each of
the following:
b)
i) Molecular formula:
ii) Condensed formula:
iii) Line-angle formula:
b)b
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8) Give the following for an straight
alkane with five carbons atoms
i)
Molecular formula:
ii)
Condensed formula:
iii)
Line-angel formula:
iv)
IUPAC name:
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Nomenclature: Unbranched or straight chain alkanes
General molecular formula: CnH2n+2
All bond angles about tetrahedral carbon are approximately 109.5°
N ame
Molecular
Formula
methane CH4
ethan e
C2 H6
propane C3 H8
bu tane
C4 H1 0
pen tane C5 H1 2
hexan e
C6 H1 4
hep tane C7 H1 6
octane
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N ame
Molecular
Formula
nonane
C9 H2 0
decan e
C1 0 H2 2
dodecan e
C1 2 H2 6
tetrad ecane
C1 4 H3 0
hexadecane C1 6 H3 4
octadecan e C1 8 H3 8
eicosane
C2 0 H4 2
C8 H1 8
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Nomenclature: Unbranched or straight chain alkanes
General molecular formula: CnH2n+2
All bond angles about tetrahedral carbon are approximately 109.5°
N ame
Molecular
Formula
methane CH4
ethan e
C2 H6
propane C3 H8
bu tane
C4 H1 0
pen tane C5 H1 2
hexan e
C6 H1 4
hep tane C7 H1 6
octane
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N ame
Molecular
Formula
nonane
C9 H2 0
decan e
C1 0 H2 2
dodecan e
C1 2 H2 6
tetrad ecane
C1 4 H3 0
hexadecane C1 6 H3 4
octadecan e C1 8 H3 8
eicosane
C2 0 H4 2
C8 H1 8
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Rules of IUPAC Nomenclature of Branched Alkanes
Parent name: the longest carbon chain
Substituent: a group bonded to the parent chain
Alkyl group: a substituent derived by removal of a hydrogen
from an alkane; given the symbol R- written in alphabetical
order
CH4 becomes CH3- (methyl)
CH3CH3 becomes CH3CH2- (ethyl)
Prefixes: di-, tri-, tetra-, etc. are not included in
alphabetization
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Naming Branched Alkanes
Parent name: the longest carbon chain
Substituent: a group bonded to the parent chain
Alkyl group: a substituent derived by removal of a hydrogen
from an alkane; given the symbol R- written in alphabetical
order
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Common alkyl groups
Primary H: hydrogen
attached to C atom which
is attached to one carbon
atoms
Secondary H: hydrogen
attached to C atom which
is attached to two carbon
atoms
Tertiary H: hydrogen
attached to C atom which
is attached to three
carbon atoms
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Common alkyl groups
N ame
methyl
Con dens ed
Structu ral Formula
-CH3
ethyl
-CH2 CH3
propyl
-CH2 CH2 CH3
isopropyl -CHCH3
CH3
bu tyl
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-CH2 CH2 CH2 CH3
N ame
isobu tyl
sec-butyl
Con dens ed
Structu ral Formula
-CH2 CHCH3
CH3
-CHCH2 CH3
CH3
CH3
t ert-bu tyl -CCH3
CH3
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9) IUPAC name of the following branched
alkane:
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10) Give the names of following alkyl groups:
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