1 Chapter 10 Introduction to Organic Chemistry: Alkanes 10.4 Properties of Alkanes Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings

2 Some Properties of Alkanes Alkanes are nonpolar. insoluble in water. less dense than water. flammable in air.

3 Some Properties of Alkanes Alkanes with 1-4 carbon atoms are methane, ethane, propane, and butane. gases at room temperature. used as heating fuels.

4 Some Properties of Alkanes Alkanes with 5-8 carbon atoms are liquids at room temperature. pentane, hexane, heptane, and octane. very volatile. used to make gasoline. Alkanes with 9-17 carbon atoms are liquids at room temperature have higher boiling points. are found in kerosene, diesel, and jet fuels.

5 Some Properties of Alkanes Alkanes with 18 or more carbon atoms have high molar masses. are waxy solids at room temperature. used in waxy coatings of fruits and vegetables.

6 Melting and Boiling Points of Hydrocarbons

7 Combustion In combustion reactions, alkanes react with oxygen. CO 2, H 2 O and energy are produced. Alkane + O 2 CO 2 + H 2 O + heat

8 Learning Check Write a balanced equation for the complete combustion of propane.

9 Solution Unbalanced equation C 3 H 8 + O 2 CO 2 + H 2 O Balance C C 3 H 8 + O 2 3CO 2 + H 2 O Balance H C 3 H 8 + O 2 3CO 2 + 4H 2 O Balance O C 3 H 8 + 5O 2 3CO 2 + 4H 2 O (Balanced)