Unit 4 Lesson 2 Organic Chemistry
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Unit 4 Lesson 2 Organic Chemistry
C Is for Carbon
Why does carbon form many different
compounds?
• Carbon has the ability to form a wide variety of
molecules, based on the arrangement of its
electrons.
• A carbon atom has a total of six electrons, two of
which are in an inner shell.
• The four electrons in the outer shell form bonds
with other atoms, and are called valence
electrons.
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Unit 4 Lesson 2 Organic Chemistry
Why does carbon form many different
compounds?
• Carbon atoms form bonds by sharing their valence
electrons with other atoms.
• Because carbon has four valence electrons, it can
form bonds with up to four other atoms at the
same time.
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Unit 4 Lesson 2 Organic Chemistry
Why does carbon form many different
compounds?
• Identify the location and number of valence
electrons in this model of a carbon atom.
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Unit 4 Lesson 2 Organic Chemistry
How does carbon form molecules?
• A carbon atom can form up to four single bonds at
one time, each bond containing one electron pair.
• A carbon atom can form a double bond containing
two electron pairs. Each carbon atom can form a
maximum of two double bonds.
• A carbon atom can form a triple bond containing
three electron pairs. Each carbon atom can form a
maximum of one triple bond.
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Unit 4 Lesson 2 Organic Chemistry
How does carbon form molecules?
• Identify the single, double, and triple bonds in the
molecules shown here.
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Unit 4 Lesson 2 Organic Chemistry
How does carbon form molecules?
• A carbon atom can form bonds with up to four
other carbon atoms, making it possible for long
chains of carbon atoms to form.
• These chains can spread in a straight line, or they
can branch off in other directions.
• The branches may also contain chains, which add
to the size of the molecule.
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Unit 4 Lesson 2 Organic Chemistry
The Secret Formula
What information does a chemical
formula contain?
• The letters in a chemical formula identify the
types of atoms in the molecule.
• Chemical formulas use the same one- and twoletter combinations that are used to identify
elements in the periodic table.
• Using chemical symbols lets you show the
composition of a molecule quickly.
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Unit 4 Lesson 2 Organic Chemistry
What information does a chemical
formula contain?
• A chemical formula also tells you how many of
each type of atom is present in the molecule.
• The number of each type of atom is represented
by a number written at the bottom right of the
chemical symbol.
• This number is called a subscript.
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Unit 4 Lesson 2 Organic Chemistry
What are the types of structural
formulas?
• The structural formula of a molecule shows how
the atoms in the molecule are connected to one
another.
• A full structural formula shows all of the bonds
between the atoms of a molecule.
• In a simplified structural formula, the atoms
bonded to each central carbon atom are grouped
together.
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Unit 4 Lesson 2 Organic Chemistry
What are the types of structural
formulas?
• Identify the full and simplified structural formulas,
and explain the advantages of each.
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Unit 4 Lesson 2 Organic Chemistry
It’s All Organic
Where are organic compounds found?
• An organic compound is a chemical compound
that is composed of carbon, hydrogen, and
possibly other elements.
• Many non-living things we use every day are
made of organic compounds, such as nylon and
heating fuel.
• Living things are also made up of organic
compounds. They provide energy and structure
for living things to grow and change.
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Unit 4 Lesson 2 Organic Chemistry
What other elements make up organic
compounds?
• Organic compounds are usually composed of
mostly carbon and hydrogen.
• They can also include other elements, such as
fluorine, chlorine, oxygen, phosphorus, nitrogen,
and sulfur.
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Unit 4 Lesson 2 Organic Chemistry
Shhh … It’s Classified!
How are organic compounds classified?
• Chemists classify organic compounds based on
their composition and structure.
• Three of the classes of organic compounds are
hydrocarbons, organic acids, and carbohydrates.
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Unit 4 Lesson 2 Organic Chemistry
How are organic compounds classified?
• A hydrocarbon is an organic compound that
contains only carbon atoms and hydrogen atoms.
• The simplest hydrocarbon is methane, CH4, which
has just one carbon atom bonded to four
hydrogen atoms.
• Some hydrocarbons have more than 20 carbon
atoms. Most long-chain hydrocarbons are found in
oils and waxes.
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Unit 4 Lesson 2 Organic Chemistry
How are organic compounds classified?
• An organic acid is an organic compound that has
acidic properties.
• Organic acids are identified by a group of atoms
called a carboxyl group: COOH.
• In a carboxyl group, one oxygen atom is doublebonded to the carbon atom, and the other oxygen
atom is single-bonded to the carbon and hydrogen
atoms.
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Unit 4 Lesson 2 Organic Chemistry
How are organic compounds classified?
• A carbohydrate is a neutral organic compound
containing carbon, hydrogen, and oxygen. There
are usually two hydrogen atoms for every oxygen
atom.
• Carbohydrates are one of nature’s energy stores.
• Carbohydrates can be simple or complex. Simple
carbohydrates are small sugar molecules, while
complex carbohydrates are long chains of sugar
molecules.
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Unit 4 Lesson 2 Organic Chemistry
What other structures can organic
compounds form?
• A ring of carbon atoms can form from three or
more carbon atoms.
• Some molecules include rings formed from six
carbon atoms that are connected by alternating
double and single bonds.
• These compounds are called aromatic compounds.
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Unit 4 Lesson 2 Organic Chemistry
What other structures can organic
compounds form?
• Polymers are molecules composed of the same
repeating small groups of atoms joined together
in long chains.
• The small units are called monomers.
• Some people think the words plastic and polymer
mean the same thing, but not every polymer is a
plastic. Some molecules essential for life, such as
nucleic acids, are polymers.
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Unit 4 Lesson 2 Organic Chemistry
What other structures can organic
compounds form?
• Identify the monomer units in this partial chain of
the polymer polyvinyl chloride.
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Unit 4 Lesson 2 Organic Chemistry
Technology Can Be Organic
• Many flat panel screens on electronic devices use
organic compounds in a device called an organic
light emitting diode (OLED).
• An OLED display doesn’t need to be lit from
behind, so the screens can be thinner and lighter.
• OLED panels do not have to be flat—they can also
be curved or folding.
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Unit 4 Lesson 2 Organic Chemistry
Technology Can Be Organic
• The OLED panels are made of several layers of
material that conduct electric current.
• When a current passes through the organic layers,
light is emitted.
• Some organic layers are composed of small
organic molecules, while other layers are
composed of polymers.
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