GeneralBiologyOnline
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General
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Ch. 4 Carbon and the Molecular Diversity of Life
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2. Carbon atoms are the most versatile building blocks of molecules
We will start with the smallest organic molecule,
methane, and build larger and more diverse molecules by adding one carbon
to the backbone at a time.
methane ( CH4).
Methane: one carbon covalently bonded to
four hydrogen's.
(Copy the structural formula for a methane
molecule in the space below or
on a separate sheet of paper.)
To see methane drawn showing electrons and orbital, click here.
Add one carbon and two hydrogen's and you have
ethane, (C2H6).
(Copy the ethane molecule's structural formula.)
Add another carbon and two hydrogen's and you
have propane (C3H8).
(Draw propane.)
(What is propane commonly used for?_______________)
Recall: there is a lot of energy stored in a high
energy electron in the covalent bond between carbon and hydrogen.
As an aid to remembering this:
(Draw an "e-" over the covalent
bonds in your structural formula of propane.)
like this
Add another carbon and two hydrogen's and you
have butane (C4H10).
(Draw butane.)
Fig. 4.4 in your
textbook shows how longer carbon backbones can be arranged in a ring.
Notice how they abbreviate these rings using only lines to illustrate the
shape. A "benzene ring" and its abbreviated structural formula are
shown below.
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6-carbon ring
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6-carbon ring
abbreviated
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Steroids, testosterone and estrogen, (Fig.
4.8, pg.57) are made up predominately of carbon rings.
Next lets look at the overall shape of these molecules
using ball-and-stick models and space-filling models.
Summary: Students should write summary
statements below as bullet points.
next
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