http://www.ck12.org Chapter 9. Chemistry of Carbon
9.2 Hydrocarbons
Lesson Objectives
- Define hydrocarbon.
- Describe and give examples of saturated hydrocarbons.
- Describe and give examples of unsaturated hydrocarbons.
- Identify uses and sources of hydrocarbons.
Lesson Vocabulary
- alkane
- alkene
- alkyne
- aromatic hydrocarbon
- hydrocarbon
- isomer
- saturated hydrocarbon
- unsaturated hydrocarbon
Introduction
Look at the pictures inFigure9.6. Each one shows an item that you might have used or seen used by someone
else. All of the items have something in common. Can you guess what it is? They all depend on carbon compounds
known as hydrocarbons.
What Are Hydrocarbons?
Hydrocarbonsare compounds that contain only carbon and hydrogen. Hydrocarbons are the simplest type of
carbon-based compounds. Nonetheless, they can vary greatly in size. The smallest hydrocarbons have just one or
two carbon atoms, but large hydrocarbons may have hundreds. The size of hydrocarbon molecules influences their
properties. For example, it influences their boiling and melting points. As a result, some hydrocarbons are gases at
room temperature, while others are liquids or solids. Hydrocarbons are generally nonpolar and do not dissolve in
water. In fact, they tend to repel water. That’s why they are used in floor wax and similar products.
Hydrocarbons can be classified in two basic classes. The classes are saturated hydrocarbons and unsaturated
hydrocarbons. This classification is based on the number of bonds between carbon atoms. You can learn more
about both types of hydrocarbons at this URL: http://www.youtube.com/watch?v=l9ZieYdLwfo (6:41).