Chapter 23 – Organic Compounds Name_________________

Simple organic compounds

Organic compounds are made from carbon.

Most compounds that contain the element carbon are organic compounds made by living organisms or synthesized in laboratories.o More than 90 % of carbon compounds are organic. o Others like carbon dioxide and the carbonates are inorganic

(not organic) compounds With 4 electrons in its outer energy level, carbon can form one

covalent bond with each of these electrons. There are many C compounds because C can form so many bonds. Some are small like the ones used as fuel while some are complex

like those in medicine and plastics. C atoms can bond together as chains, branched chains, & rings.

o The first structure shows carbon bonded in a straight chain as heptane, an organic compound in gasoline.

o The second structure, a branched chain, shows isoprene, an organic compound in natural rubber.

o The third structure, a cyclic ring or chain, is vanillin from vanilla flavoring.

Carbon can form single, double, and triple bonds.

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Representations: organic molecules can be represented by their chemical formulas, structural formulas, or space-filling models.

CH4

Hydrocarbons

A compound that is made of only carbon and hydrogen is called a hydrocarbon.

Natural gas contains the hydrocarbon methane or CH4. Hydrocarbons produce more than 90% of the energy we use. Hydrocarbons are in medicines, foods, clothing, gasoline, and many

many others

Hydrocarbon lengths

The number of carbon atoms is indicated by the root of its name. See the table:

Methane has _____ carbons

Propane has _____ carbons

Octane has _____ carbons

Pentene has _____ carbons

Hexyne has ______ carbons

The ending tells the kinds of bonds

-ane means _____________________

-ene means _____________________

-yne means _____________________

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How does the number of carbons affect the boiling point?

See graph: As the number of carbons increases, the boiling point ________.

What is the boiling point of methane?

What is the boiling point of pentane?

Hydrocarbons with only single-bonded C atoms are called saturated hydrocarbons. It is saturated because each C is bonded to as many H as possible.

Hydrocarbons with multiple (double or triple) bonds are called unsaturated hydrocarbons.

Isomers are compounds that have identical chemical formulas but different molecular structures and shapes. They have different boiling points, melting points, and densities.

Generally, the more “branched” an isomer is, it will have lower boiling and melting points.

The isomers of pentane (C5H12) are:

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Boiling point 36°C 28°C 9.5°CMelting point -130°C -160°C -17°CDensity 0.626 g/mL 0.620 g/mL 0.614 g/mL

Other isomers

There are tons of isomers in organic chemistry. It gets very complicated.

Isomers of butane are:

Carbon rings

Carbon readily forms ring structures. They have “cyclo” as part of their name. Cyclo- means circular. These are called “cyclic hydrocarbons”.

Five and six membered rings are very common in nature.

cyclopropane cyclobutane _____________ _________________

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Benzene (C6H6) is a special ring structure with alternating double and single bonds. It can also be shown as a circle in a hexagon. It very stable and unreactive.

Benzene can fuse together into double ring structures, such as naphthalene, found in mothballs.

Substituted hydrocarbonsA substituted hydrocarbon has one or more of its hydrogen atoms replaced by other atoms or groups of atoms.

A functional group is a groups of atoms that behaves a certain way

ethaneethanol acetic acid

functional group : –C-O-H

An alcohol is formed when –OH replaces one or more hydrogen atoms

Ex: drinking alcohol, rubbing alcohol, sugars

An organic acid is formed when –COOH replaces one of the hydrogen atoms

Ex: vinegar, citric acid, lactic acid

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An ester is formed when –COOC- replaces a hydrogen. It results when an organic acid reacts with an alcohol. Esters are found in artificial flavorings and perfumes

Banana oil (isopentyl acetate) can be made in the lab.

This chemical is also found in bee stings. It helps attract other bees to join in the attack.

Amines form when –NH2 replaces a hydrogen atom. Used in protein formation and making dyes.

Mercaptans form when –SH replaces a hydrogen atom. They usually smell really bad due to the sulfur, but the smell of grapefruit is also due to mercaptans.

Halocarbons form when a halogen (F, Cl, Br, I) replace a hydrogen. Teflon, used in nonstick cookware, has fluorine in it.

Aromatic compounds contain benzene rings. Many have distinctive smells. Examples are found in almonds, cloves, cinnamon, wintergreen, vanilla.

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Petroleum – A Source of Organic CompoundsPetroleum is a mixture of hydrocarbons and other substances. It is formed from fossils and is called fossil fuel. The liquid is often called crude oil. Crude oil is dark, flammable, and foul-smelling.

Crude oil is a mixture of thousands of compounds; processing it leads to many things we use such as plastics, fuel, waxes.

Crude oil is extracted from the ground by drilling.

It is separated into its components by distillation in oil refineries in a fractionating tower. It separates by boiling points.

Uses

The lightest fractions are gases used as fuels. The middle fractions are liquid fuels. The heavy fractions are used in oils, tars, asphalts.

Further processing turns these into ink, flavorings, aspirin, insecticides, dyes, and many other things.

Polymers

Polymers are long chains of carbon atoms. The specific units are called monomers.

A monomer is a small molecule that can combine itself repeatedly to form the long chain.

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Polymers are used to make plastics, fibers, backpacks, and many other things.

PE, Polyethylene used in plastic bags, plastic bottles

PVC, Polyvinyl chloride used in plastic pipes, garden hoses

PP, Polypropylene used in glues, carpets, clothing

PS, Polystyrene used in Styrofoam, cd cases

PU, Polyurethane used in waterproof coatings

Polyesters are a general term. They are used in making fabrics.

Disposing of polymers is a big problem, as they do not decompose naturally. Recycling is important. Depolymerization is a process that uses heat or chemicals to break down polymers into their monomers.

Biological CompoundsIn biology, macromolecules were discussed. They are biological polymers.

Proteins are large organic polymers made from amino acid monomers.

Two or more amino acids combine to form a peptide and lose water in the process. Peptides with about 50 or more amino acids are called proteins.

The pictures shows two amino acids combining to form a dipeptide.

Hemoglobin is an important protein that carries oxygen in your blood.

Proteins are found in meats and dairy; your body breaks them down into the amino acids that go into forming muscle tissue.

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Carbohydrates are compounds made from carbon, hydrogen, and oxygen. They include starches and sugars.

Sugars are generally sweet.

Their names end in –ose.

Examples are

glucose (blood sugar), fructose (fruit sugar), lactose (milk sugar), sucrose (table sugar).

They provide quick energy.

Starches are polymers. The monomers are glucose. They provide long-term energy.

Lipids are fats and oils. They include butter, vegetable oils, shortening. Fats are usually saturated and oils are usually unsaturated.

Fats and oils have a long chain of carbon atoms.

Cholesterol is a lipid found in meats, butter, cheese, fish. Cholesterol is found in animal sources. Your body produces cholesterol.

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Nucleic Acids are organic polymers found in DNA and RNA.

DNA stands for DeoxyriboNucleic Acid.

RNA stands for RiboNucleic Acid

Nucleotides are the monomers that make up nucleic acids. They contain a nitrogenous base (adenine, thymine, cytosine, and guanine), a sugar, and a phosphate group.

DNA fingerprinting is now used to identify individuals.

Human DNA contains more than five billion base pairs and is unique for each individual.

In the example shown, the crime scene DNA can be matched to suspect #2

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