Chapter 10

Homework:10.13, 10.17, 10.18, 10.19, 10.24, 10.25,10.27, 10.29, 10.30, 10.32, 10.34, 10.35, 10.41

Organic Chemistry

• Organic Chemistry- the chemistry of compounds of carbon

• Organic compounds mainly have carbon and only a few other elements such as hydrogen, oxygen, and nitrogen

• Some may contain sulfur, halogens, or phosphorus as well

Early Days

• Early on, organic molecules where thought to only come from living organisms

• It was believed that a “vital force” was needed to create organic molecules

• A chemist could not synthesize an organic molecule from inorganic ones.

Friedrich Wöhler

• Friedrich Wohler disproved this by heating Ammonium Chloride and Silver Cyanate, both inorganic compounds, and got urea, an organic compound found in urine

NH4Cl + AgNCO

NH2 NH2

O

Urea

+ AgCl

Today, approx. 85% of all known compounds are Organic!!!

Sources of Organic Compounds

1) Isolation from Nature

-Living organisms are chemical “factories”

- Each plant, animal, microorganism, etc, makes thousands of organic compounds by a process called biosynthesis

- These compounds can be extracted and isolated from these biological sources

Sources of Organic Compounds

2) Synthesis in the laboratory

-organic chemist strive to develop more ways to make the same compounds found in nature

-Compounds made in a lab are identical to those found in nature, assuming they are pure

• Chemists not only synthesize compounds found in nature, but also create molecules not found in nature.

• The majority of the more than 10 million known organic molecules are purely synthetic and do not exist in living organisms.

Structure of Organic Molecules

• A structural Formula shows all atoms present in a molecule as well as the bonds that connect the atoms to each other.

Ex.

C2H5OH

H C C

H

H

H

H

O H

• Table 10.2 shows several covalent compounds containing carbon bonded to H, O, N, and Cl

• You are responsible for knowing the name, structural Formulas, and bond angles for these molecules!!

Typical Bonding• From this table, we can see the following:

– Carbon normally forms 4 covalent bonds and has no unshared pairs of electrons

– Nitrogen normally forms 3 covalent bonds and has 1 unshared pair of electrons

– Oxygen normally forms 2 covalent bonds and has 2 unshared pairs of electrons

– Hydrogen normally forms 1 covalent bond and has no unshared pairs of electrons

– Halogens normally forms 1 covalent bond and have 3 unshared pairs of electrons

Example 10.1

• This would be a good test question:

Functional Groups• Functional Group- an atom or group of atoms

within a molecule that shows a characteristic set of physical and chemical properties.

• While organic compounds can undergo a wide variety of chemical reactions, only certain portions of their structures are changed in any particular reaction.

• The part that undergoes chemical reactions are functional groups.

• The same functional group will undergo the same type of reaction regardless of the molecule it occurs in!!!!

• Therefore, we don’t have to study individual compounds, we can identify only a few characteristic functional groups and then study the chemical reactions that each undergoes!!

• Functional groups also serve as the basis for naming organic compounds

Functional Group Summary

• They are sites of chemical reactions

• Determine in large measure the physical properties of a compound

• Are the units by which we divide organic compounds into families

• Serve as the basis for naming organic molecules.

Five Common Function Groups

Functional

Family Group Example Name

Alcohols

• The functional group of an alcohol is an -OH group, the hydroxyl group, bonded to a tetrahedral carbon.

• Alcohols are classified as 1o (primary), 2o (secondary), and 3o (tertiary) depending on the number of carbon atoms bonded to the carbon bearing the -OH group.

• Examples:

Amines

• The functional group of an amine is an amino group.

• Amino group- a nitrogen atom bonded to one, two, or three carbon atoms.

• Example:

• Amines are classified as primary, secondary, or tertiary Based on the number of carbons bonded to the nitrogen!!

• This is different than alcohols!!!

• Examples:

Aldehydes and Ketones

• Both contain an oxygen double bonded to a carbon, this is called a carbonyl group.

• In Aldehydes, the carbonyl is bonded to at least one hydrogen

• In Ketones, the carbonyl is bonded to two carbon groups.

Carboxylic Acids

• The functional group for Carboxylic Acids is -COOH, the carboxyl group