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CHEM1: Organic Chemistry
CHAPTER 1: INTRODUCTION AND REVIEW
Organic Chemistry started as the chemistry of life, then that
was thought to be different from the chemistry in the
laboratory. Then it became the chemistry of carbon compounds,
especially those found in coal. But now it is both. It is the
chemistry of the compounds formed by carbon and other
elements such as are found in living things, in the products of
living things, and wherever else carbon is found.
TAKE NOTE: ORGANIC CHEMISTRY is carbon centric. Carbon is
the key atom on all these molecules and carbon atoms do some
very predictable things, like make or form bonds.
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Urea- is the main nitrogen containing part if urine that
comes from our body’s metabolic breakdowns of proteins.
But it’s also a great fabric dye mordant which is a
chemical that makes the dye last longer often enhances
the color.
In the 19th century, experiments showed that organic
compounds could be synthesized from inorganic compounds.
1828- the German chemist Friedrich Wohler converted
ammonium cyanate, made from ammonia and cyanic acid, to
urea simply by heating it in the absence of oxygen.
Today, organic chemistry is defined as the study of the
structure, properties, composition, reactions, and preparation of
carbon-containing compounds. This definition includes
chemicals extracted from living things, but also man-made
polymers, like plastics.
A BRIEF HISTORY
The term organic literally means “derived from living
organisms”.” Originally, the science of organic chemistry was
the study of compounds extracted from living organisms and
their natural products.
Compounds such as sugar, urea, starch, waxes, and plant oil
were considered “organic”, and people accepted Vitalism, the
belief that natural products needed a “vital force” to create
them.
Chemists have learned to synthesize pr simulate many of these
complex molecules. The synthesized products serve as drugs,
medicines, plastics, pesticides, paints, and fibers. Many of the
most important advances in medicine are actually advances in
organic chemistry. New synthetic drugs are developed to
combat disease, and new polymers are molded to replace failing
organs. Organic chemistry has gone full circle. It began as the
study of compounds derived from “organs”, and now it gives us
the drugs and materials we need to save or replace those
organs.
PRNCIPLES OF ATOMIC STRUCTURE
nucleus, but it is the electrons that take part in chemical
bonding and reactions.
Types of Chemical Bonds
Chemical bonding describes a variety of interactions that hold atoms
together in chemical compounds.
Key Points
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ATOMS- are made up of protons, neutrons, and electrons.
Atoms are the fundamental building blocks of chemistry.


Matter itself is made of a collection of different types of
atoms.
Scientists discovered 118 kinds of atoms which we call
ELEMENTS.
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Key Terms

PROTONS- are positively charged and are found together with
(uncharged) neutrons in the nucleus.

ELECTRONS- which have a negative charge that is equal in
magnitude to the positive charge on the proton, occupy the
spaced surrounding the nucleus.

Protons and Neutrons- have similar masses, about 1800 times
the mass of an electron. Almost all the atom’s mass is in the
Chemical bonds are forces that hold atoms together to make
compounds or molecules.
Chemical bonds include covalent, polar covalent, and ionic
bonds.
Atoms with relatively similar electronegativities share electrons
between them and are connected by covalent bonds.
Atoms with large differences in electronegativity transfer
electrons to form ions. The ions then are attracted to each
other. This attraction is known as an ionic bond.

bond: A link or force between neighboring atoms in a molecule
or compound.
ionic bond: An attraction between two ions used to create an
ionic compound. This attraction usually forms between a metal
and a non-metal.
covalent bond: An interaction between two atoms, which
involves the sharing of one or more electrons to help each atom
satisfy the octet rule. This interaction typically forms between
two non-metals.
intramolecular: Refers to interactions within a molecule.

intermolecular forces: Refers to interactions between two or
more molecules.
Chemical bonds
Chemical bonds are the connections between atoms in a molecule.
These bonds include both strong intramolecular interactions, such as
covalent and ionic bonds. They are related to weaker intermolecular
forces, such as dipole-dipole interactions, the London dispersion
forces, and hydrogen bonding. The weaker forces will be discussed in
a later concept.
Chemical bonds: This picture shows examples of chemical bonding using
Lewis dot notation. Hydrogen and carbon are not bonded, while in water
there is a single bond between each hydrogen and oxygen. Bonds, especially
covalent bonds, are often represented as lines between bonded atoms.
Acetylene has a triple bond, a special type of covalent bond that will be
discussed later.
1. Ionic Bonding
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A transfer of one electron gives each of two elements a noble-gas
configuration. The resulting ions have opposite charges, and they
attract each other to form an ionic bond.
LEWIS STRUCTURE
- is a very simplified representation of the valence shell electrons
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2. Covalent bonding
In which electrons are shared rather than transferred, is
the most common type of bonding in organic compounds.
in a molecule. It is used to show how the electrons are
arranged around individual atoms in a molecule. Electrons are
shown as "dots" or for bonding electrons as a line between the
two atoms. The goal is to obtain the "best" electron
configuration, i.e. the octet rule and formal charges need to be
satisfied.
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