Introduction to Organic Chem. Part 1 Intro to Hydrocarbons & Naming Rules

Introduction to Organic Chem.

Part 1Intro to Hydrocarbons & Naming Rules

Organic Chemistry:The study of carbon

containing compounds

-Most of the compounds that make up your body contain carbon.

-Carbon containing compounds are often called “organic” compounds.

Carbon Compounds and Biomolecules

A trans-fatty acid

Carbon: The backbone of life• Living organisms are

made up mostly of molecules based on carbon.

• Thus the term “carbon-based life forms”.

Carbon: The backbone of life

• Americans, on average, consume 140 lbs of sugar per year, much of it in the form of fructose (High Fructose Corn Syrup),

Fructose, a hexose sugar

Carbon: The backbone of life

• Cellulose, found in plant cell walls, is the most abundant organic compound on Earth

Carbon bonding

• The small atomic size of carbon makes the bonds very strong (notice the close proximity of the electrons to the protons)

• Carbon is unparalleled in its ability to form large, complex molecules

Carbon Fiber

• High strength, but very low weight fiber.

• Used in sports and military applications

Carbon Allotropes

• When an element can take on different shapes, functions, or structures because of different bonding arrangements of the atoms, these are called allotropes.

• Diamonds, graphite, and nanotubes are all allotropes of carbon.

Nanotubes

• SUPER high strength-to-weight ratio

Hydrocarbons

Hydrocarbon Videos1. How oil is “made”

1. http://www.youtube.com/watch?v=3yn99YJXpbQ

2. Fracking, the untold story1. http://www.youtube.com/watch?v=dEB_Wwe-uBM

3. Hydrocarbon Cracking1. http://www.youtube.com/watch?v=Xsqlv4rWnEg

4. Fractional Distillation1. http://www.youtube.com/watch?v=PYMWUz7TC3A

Hydrocarbons are the simplest Organic Molecules

• Hydrocarbons are chains of Carbon surrounded by Hydrogen.

Methane, propane, etc.

Gasoline, etc.

Kerosene, etc.

Diesel, etc.

Methane, propane, etc.

Hydrocarbons are grouped into 3 classes

1. Alkanes– Only single bonds connecting

the carbon atoms in the chain

OctaneC8H12

Hydrocarbons are grouped into 3 classes

2. Alkenes– Contain at least one double bond

Hydrocarbons are grouped into 3 classes

3. Alkynes– Contain at least one triple bond

ExamplesAlkynes

Hydrocarbon skeletal structure• Sometimes, in an

effort to simplify things, we only show the “skeletal structure” of an organic molecule

• Where are the Hydrogen’s???

Butane skeletal structure

Hydrocarbon skeletal structure• When you see a naked organic skeleton, the

“joints” represent carbon atoms, and the Hydrogen atoms are left out.

Carbon

Octane skeletal structure

Hydrocarbon skeletal structure

Octane skeletal structure

The lines between the joints represent the bonds between the atoms. In this case, they are all single bonds, so this is an alkane

Bonds

What molecule do each of these skeletons represent?

1. 2.

3.

Propene Hexyne

Decane

Different Types of molecular models

• Molecules can be modeled in several different ways:– Chemical Formula– Structural Formula– Skeletal Structure– Space-filling Model

Propane modeled 5 separate ways

propane: space-filling model

propane: skeletal structure

C3H8propane: chemical formula

Introduction to Hydrocarbon Nomenclature(naming rules)

Hydrocarbon general naming formulas

CnH2n+2 = alkane

CnH2n = alkene

CnH2n-2 = alkyne

Try it out: Convert the following…

1) C3H8 ____________

2) Propyne __________3) C4H8 ____________

4) pentene __________5) C6H10 ____________

6) hexane __________

Hydrocarbons can form rings ***Note that the general formula doesn’t work now because of the ring

structure. You must look at the bond lines***

C5H10C6H12 C6H6

When a hydrocarbon forms a ring, we use the term “cyclo” to denote it

Cyclopentane Cyclohexene

Benzene is the most important ring compound

Benzene