Chemical Potential Energy Ck12 Science Say Thanks to the Authors Click http://www.ck12.org/saythanks (No sign in required) To access a customizable version of this book, as well as other interactive content, visit www.ck12.org CK-12 Foundation is a non-profit organization with a mission to reduce the cost of textbook materials for the K-12 market both in the U.S. and worldwide. Using an open-source, collaborative, and web-based compilation model, CK-12 pioneers and promotes the creation and distribution of high-quality, adaptive online textbooks that can be mixed, modified and printed (i.e., the FlexBook® textbooks). Copyright © 2016 CK-12 Foundation, www.ck12.org The names “CK-12” and “CK12” and associated logos and the terms “FlexBook®” and “FlexBook Platform®” (collectively “CK-12 Marks”) are trademarks and service marks of CK-12 Foundation and are protected by federal, state, and international laws. Any form of reproduction of this book in any format or medium, in whole or in sections must include the referral attribution link http://www.ck12.org/saythanks (placed in a visible location) in addition to the following terms. Except as otherwise noted, all CK-12 Content (including CK-12 Curriculum Material) is made available to Users in accordance with the Creative Commons Attribution-Non-Commercial 3.0 Unported (CC BY-NC 3.0) License (http://creativecommons.org/ licenses/by-nc/3.0/), as amended and updated by Creative Commons from time to time (the “CC License”), which is incorporated herein by this reference. Complete terms can be found at http://www.ck12.org/about/ terms-of-use. Printed: January 5, 2016 AUTHOR Ck12 Science www.ck12.org C HAPTER Chapter 1. Chemical Potential Energy 1 Chemical Potential Energy • Define chemical potential energy. • Give examples of chemical potential energy. Where did gunpowder come from? Gun powder was originally developed by the Chinese in the ninth century AD, primarily for rockets. This material is composed of charcoal, sulfur, and saltpeter (potassium nitrate). The reaction involves the conversion of the charcoal to carbon dioxide with the potassium nitrate providing the extra oxygen needed for a rapid reaction. Sulfur was included to stabilize the product, but gunpowder is still highly explosive. Types of Energy Two basic types of energy exist: potential energy and kinetic energy. Potential energy is stored energy. It has not yet been released, but is ready to go. Kinetic energy is energy of motion. It causes work to be done through movement. Chemical Potential Energy Energy is the capacity for doing work or supplying heat. When you fill your car with gasoline, you are providing it with potential energy. Chemical potential energy is the energy stored in the chemical bonds of a substance. The various chemicals that make up gasoline contain a large amount of chemical potential energy that is released when the gasoline is burned in a controlled way in the engine of the car. The release of that energy does two things. Some of the potential energy is transformed into work, which is used to move the car. At the same time, some of the potential energy is converted to heat, making the car’s engine very hot. The energy changes of a system occur as either heat or work, or some combination of both. 1 www.ck12.org FIGURE 1.1 A dragster is able to accelerate because of the chemical potential energy of its fuel. The burning of the fuel also produces large amounts of heat. Dynamite is another example of chemical potential energy. The major component of dynamite is nitroglycerin, a very unstable material. By mixing it with diatomaceous earth, the stability is increased and it is less likely to explode if it receives a physical shock. When ignited, the nitroglycerin explodes rapidly, releasing large amounts of nitrogen and other gases along with a massive amount of heat. FIGURE 1.2 Dynamite explosion. Summary • Chemical potential energy is energy available in the chemical bonds of a compound. Practice Questions Read the material at the link below and answer the questions: http://www.brighthubeducation.com/science-homework-help/118803-what-is-chemical-potential-energy/ 1. How is chemical potential energy released? 2 www.ck12.org Chapter 1. Chemical Potential Energy 2. Give examples of chemical potential energy. 3. What is chemical potential energy dependent upon? Review Questions 1. What is chemical potential energy? 2. How is gasoline used as kinetic energy? 3. How is dynamite used as kinetic energy? • chemical potential energy: The energy stored in the chemical bonds of a substance. • kinetic energy: Energy of motion. • potential energy: Stored energy. References 1. Mike Cumpston (Wikipedia: Mcumpston). http://commons.wikimedia.org/wiki/File:Hawken_Rifle.jpg . 2. Image copyright Juerg Schreiter, 2014. http://www.shutterstock.com . Used under license from Shutterstock.com 3. Courtesy fo the US Marine Corpos. http://commons.wikimedia.org/wiki/File:USMC-10955.jpg . 3