Organic Chemistry & Intermolecular Forces

Alcohol

ol

Ether

yl ether

Aldehyde

al

Ketone

one

Carboxylic Acids

oic acid

ester

ate

amine

yl amine

Hydrocarbon

Compounds composed of only carbon and hydrogen

All can be considered nonpolar → Only contains London Dispersion forces

Saturated hydrocarbon

C-C bonds are all single bonds (alkane)

Alkane

Type of bonding between carbon atoms that only are single bonds

Unsaturated Hydrocarbon

C-C bonds contain multiple bonds (alkene, alkyne)

Alkene

Type of bonding between carbon atoms that are double bonds

Alkyne

Type of bonding between carbon atoms that are triple bonds

Structural isomer

Occurs when two molecules have the same atoms but different bonds

Organic Chemistry Prefix: 1

meth

Organic Chemistry Prefix: 2

eth

Organic Chemistry Prefix: 3

pro

Organic Chemistry Prefix: 4

bu

Prefix: 5

pent

Prefix: 6

hex

Prefix: 7

hept

Prefix: 8

oct

Prefix: 9

nona

Prefix: 10

deca

Methane

1 carbon

CH₄

Ethane

2 carbons

C₂H₆

Propane

3 carbons

C₃H₈

Butane

4 carbons

C₄H₁₀

Pentane

5 carbons

C₅H₁₂

Hexane

6 carbons

C₆H₁₄

Heptane

7 carbons

C₇H₁₆

Octane

8 carbons

C₈H₁₈

Nonane

9 carbons

C₉H₂₀

Decane

10 carbons

C₁₀H₂₂

Methyl

-CH₃

ethyl

-CH₂CH₃

propyl

-CH₂CH₂CH₃

butyl

-CH₂CH₂CH₂CH₃

Cyclic alkanes

Carbon atoms that form rings containing only C-C single bonds

Basic Intermolecular Forces

Hydrogen Bonds

Dipole-Dipole

London Dispersion Bonds

Stronger IMFs mean

• High Boiling Point

• High Melting Point

• Lower Vapor Pressure

Synthetic polymers

Plastics

Teflon

Polybinylchloride (PVC)

Nylon

Kevlar

Naturally occurring polymers

Proteins

Nucleic acids (DNA, RNA)

VSEPR

• Electrons arrange themselves in a molecule so as to be as far apart as possible

• Shared electrons pairs repel one another

• Lone Pairs occupy a slightly larger orbital than shared electrons, so shared bonding orbitals are pushed together slightly by lone pairs

Nonpolar Covalent

Equal sharing of electrons between the two elements

≤ 0.3

Symmetric molecule

Polar covalent bond

Unequal sharing of electrons

0.4 < x < 1.7

Greater the electronegativity, the more polar the bond

Asymmetric molecule

Intermolecular Forces

Attractive forces that hold identical molecules together

London Dispersion Forces

Weakest IMF

Dominant force of attraction between identical nonpolar molecules

Weakest due to forces being temporary

Additive property → the larger the molecule (mass), the greater the effect

Present in all covalent molecules

Dipole-Dipole Forces

Medium strength IMF

Attraction between oppositely charged regions of polar molecules

Hydrogen Bonds

Strongest IMF

Attraction between polar molecules

Exists when hydrogen is bonded to FON

Ionic bonds

between metal and nonmetal

Covalent bonds

Between nonmetal and nonmetal

Metallic bonds

Between atoms of the same metal