1. Alkanes C H n 2n+2 all C are sp3 hybridized  bonds n root suffix
formula
3 prop ane C3H8
4 but ane C4H10
5 pent ane C5H12
6 hex ane C6H14
7 hept ane C7H16
8 oct ane C8H18
9 non ane C9H20
10 dec ane C10H22 1
meth
ane C H 4 2
eth
ane
C2H6

2. Alkanes n = 1-4 gases n = 5-15 liquids n > 15 solids compound m.w.
b.p.(Co) CH
C2H
C3H
C4H
C5H
n = gases
n = liquids
n > solids

3. Alkanes IMF = q1q2 n = 1-4 gases r n = 5-15 liquids n > 15 solids
____ r
n = liquids
n > solids
q 
# electrons
instantaneous dipole moments - + + -

4. Alkanes IMF = q1q2 r 72 36.1 72 27.9 72 9.5 structural isomers
____
compound
m.w.
b.p. 72
36.1 72
27.9 72
9.5
structural isomers
same formula
different shape
r 
branching

6. Reactions of Alkanes combustion __ C3H8 + __ O2  5 __ CO2 + 3 __ H2O4
exothermic reaction
combustion with insufficient O2
__ C3H8 + __ O2  __ CO + __ H2O 3 4
7/2
improperly vented spaces and cigarettes

7. Reactions of Alkanes Substitution of halogens
Cl2  2Cl.
step 1
initiation
step 2
Cl.+ CH4  CH3. + HCl
propagation
step 3
CH3.+ Cl2  CH3Cl + Cl.
propagation
step 4
Cl.+ Cl.  Cl2
termination
get a mixture of chlorinated methanes

8. Halogenation of Alkanes
CH3Cl
chloro
methane
methyl chloride
CH2Cl2 di
chloromethane
methylene chloride
CHCl3
tri
chloromethane
chloroform
CCl4
tetra
chloromethane
carbon tetrachloride
all liquids at room temperature
methane is gas
e- rich Cl increases LDF

9. Nomenclature 1. Pick longest C chain as parent
2. Number C beginning at end with first branch
3. Identify branching substituents
Assign each a number
4. Use commas to separate numbers
hyphens to separate numbers from names
5. Alphabetize substituents

10. Nomenclature Structural isomers of C5H12 I. III. II. I. pentane II. 2-4 1 3 2 1 2 2 3 3 4 4
II. 1 1 2 3 I.
pentane
II. 2-
methyl
butane
III.
2,2- di
methyl
propane

11. Nomenclature R = “alkyl” group 1o 3o primary carbon tertiary carbon 4o
secondary carbon
quaternary carbon

12. Nomenclature “common” names to learn: iso propyl alphabetized as i
sec-
butyl
alphabetized as b
iso
butyl
alphabetized as i
tert-
butyl
alphabetized as b