Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Chapter 10 Introduction to Organic Chemistry: Alkanes 10.4 Properties of Alkanes 1

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Some Uses of Alkanes Alkanes with one to four carbons are gases at room temperature and are widely used as heating fuels. methane, ethane, propane, butane Butane has four carbons: Alkanes with five to eight carbons are highly volatile liquids at room temperature, making them useful in fuels such as gasoline. pentane, hexane, heptane, octane Octane has eight carbons: 2

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Some Uses of Alkanes Alkanes with 9−17 carbons are liquids with higher boiling points and are found in motor oils, mineral oil, kerosene, diesel, and jet fuels. Decane has 10 carbons: 3

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Some Uses of Alkanes Alkanes with 18 or more carbon atoms have high molar masses are waxy solids at room temperature are used in waxy coatings of fruits and vegetables 4

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Solubility and Density of Alkanes Alkanes are nonpolar insoluble in water less dense than water flammable in air The crude oil in oil spills floats on top of the water, forming a thin layer on the surface because it is less dense than water. 5

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Combustion of Alkanes Alkanes have strong C  C bonds react with oxygen gas to make carbon dioxide and water in combustion reactions release energy when C  C bonds are broken in combustion reactions CH 4 (g) + 2O 2 (g)  CO 2 (g) + 2H 2 O(g) + energy 6

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Alkane Mixtures in Crude Oil An oil refinery turns crude oil into usable fuel, producing natural gas, gasoline, kerosene, lubricant oils, and asphalt. 7

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Alkane Mixtures in Crude Oil 8

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. Learning Check Propane is a fuel often used in barbeques. Write a balanced equation for the complete combustion of propane. 9

Chemistry: An Introduction to General, Organic, and Biological Chemistry, Eleventh Edition Copyright © 2012 by Pearson Education, Inc. 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) 10