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