Foundations of College Chemistry PDF

Foundations of College Chemistry Fifteenth Edition Morris Hein, Susan Arena, and Cary Willard Chapter 1 An Introduction to Chemistry This slide deck contains animations. Please disable animations if they cause issues with your device. An Intro...

Foundations of College Chemistry Fifteenth Edition Morris Hein, Susan Arena, and Cary Willard Chapter 1 An Introduction to Chemistry This slide deck contains animations. Please disable animations if they cause issues with your device. An Introduction to Chemistry The vibrant colors of the aurora borealis are the result of chemistry in our atmosphere. Copyright ©2016 John Wiley & Sons, Inc. 2 Chapter Outline 1.1 The Nature of Chemistry A. Thinking Like a Chemist 1.2 A Scientific Approach to Problem Solving A. The Scientific Method 1.3 The Particulate Nature of Matter A. Physical States of Matter 1.4 Classifying Matter A. Distinguishing Mixtures from Pure Substances Copyright ©2016 John Wiley & Sons, Inc. 3 Learning Objectives: State the definition of chemistry and why the study of chemistry is important Describe the steps involved in the scientific method Describe the characteristics of matter, including the state of matter Distinguishing among a pure substance, homogeneous mixture , and a heterogenous mixture Copyright ©2016 John Wiley & Sons, Inc. 4 1.1 The Nature of Chemistry Chemistry is the science of matter. Chemistry deals with the composition, structure, properties, reactions and energetics of matter. Matter is any object that has mass and occupies space. Copyright ©2016 John Wiley & Sons, Inc. 5 Chemistry the Central Science Chemistry is interconnected to a vast array of other STEM disciplines 6 Chemistry and Everyday Life Examples of chemistry in everyday life: Digesting food Synthesizing polymers for clothing, cookware, and credit cards Refining crude oil into gasoline and other products As you proceed through this course, you will discover: Many different examples of changes in the composition and structure of matter. How to classify these changes in matter and understand how they occur. The changes in energy that accompany these changes in matter. 7 Thinking Like a Chemist Chemists try to understand how and why chemical changes occur in nature and the human body. Chemists try to explain the macroscopic world, which is observable to the eye… …and the microscopic world, which is made up of objects too small to see, like atoms and molecules. Copyright ©2016 John Wiley & Sons, Inc. 8 A Microscopic View of Water Imagine holding one molecule of water in your hand. What does it look like? Water (H2O) is composed of two hydrogen atoms and one oxygen atom. Copyright ©2016 John Wiley & Sons, Inc. 9 1.2 A Scientific Approach to Problem Solving Observation Results not consistent becomes with prediction scientific laws 1 2 Form 3 Perform Contributes Observation hypothesis; experiment; to body of and make make more knowledge curiosity prediction observations 4 Modify the A well-stablished hypothesis hypothesis becomes theory Image adapted from 10 1.3 The Particulate Nature of Matter Matter appears in many forms, both big and small. On the microscopic level, all matter is composed of discrete, tiny fundamental particles called atoms. Using a scanning tunneling microscope, individual atoms can be configured into specific arrangements. Copyright ©2016 John Wiley & Sons, Inc. 11  Physical States of Matter (1 of 6) Matter: Anything that occupies space and has mass. Matter exists as three physical states: solid, liquid, and gas. Copyright ©2016 John Wiley & Sons, Inc. 12 Solid States of Matter (2 of 6) A solid has definite shape and volume which can be independent of its container. The most common solids are crystalline and have regular, repeating three-dimensional geometric patterns. Solid water molecules are held together rigidly and are very close to each other. Copyright ©2016 John Wiley & Sons, Inc. 13 Physical States of Matter (3 of 6) Some solids such as plastics, glass and gels do not have regular, internal geometric patterns. Copyright ©2016 John Wiley & Sons, Inc. 14 Liquid States of Matter (4 of 6) A liquid has definite volume but not a definite shape. Liquid particles are held together by strong attractive forces and are able to move freely. Liquids are fluid which allows them to take the shape of the container. Liquid water molecules are close together but are free to move around and slide over each other. Copyright ©2016 John Wiley & Sons, Inc. 15 Gas States of Matter (5 of 6) A gas has indefinite volume and no fixed shape. Gas particles move independently and are relatively far apart, which allows them to completely fill a container. Gases can be compressed or expanded almost indefinitely. Gaseous water molecules are far apart and move freely and randomly. Copyright ©2016 John Wiley & Sons, Inc. 16 Physical States of Matter (6 of 6) Although matter is separated into discrete units, attractive forces hold the particles together and give matter its appearance of continuity. Attractive forces are strongest in solids, giving them rigidity; weaker in liquids but strong enough to maintain definite volumes; and weakest in gases which allows them to behave nearly independently. Copyright ©2016 John Wiley & Sons, Inc. 17 Physical States of Matter (4 of 4) Table 1.1 Common Materials in the Solid, Liquid, and Gaseous States of Matter Solids Liquids Gases Aluminum Alcohol Acetylene Copper Blood Air Gold Gasoline Butane Polyethylene Honey Carbon dioxide Salt Mercury Chlorine Sand Oil Helium Steel Syrup Methane Sugar Vinegar Nitrogen Sulfur Water Oxygen Copyright ©2016 John Wiley & Sons, Inc. 18 1.4 Classifying Matter: Pure substance or Mixture A pure substance has a definite, fixed composition. Elements: Pure substance that cannot be broken down into simpler substances by chemical changes. Consist of one type of element Examples: Gold (Au), Phosphorus (P), Oxygen (O) Compounds: Pure substances that can be broken down into simpler substances by chemical changes. Consist of two or more types of elements chemically bonded Examples: H2O, C6H12O6, AgCl The properties of compounds are different from the uncombined elements making up the compound. Copyright ©2016 John Wiley & Sons, Inc. 19 Mixtures A mixture is a combination of two or more pure substances. There are two types of mixtures: homogenous mixtures and heterogeneous mixtures. Copyright ©2016 John Wiley & Sons, Inc. 20 Separation of Mixtures The components of a mixture do not lose their identities and may be separated by physical means such as: boiling, filtration, floatation, magnetism. Copyright ©2016 John Wiley & Sons, Inc. 21 Let’s Practice! (1 of 6) Which of the following is a heterogeneous mixture? a. baking soda b. gasoline c. grape juice d. copper metal e. soil Copyright ©2016 John Wiley & Sons, Inc. 22 Let’s Practice! (2 of 6) Which of the following is a heterogeneous mixture? a. baking soda b. gasoline c. grape juice d. copper metal e. Answer: soil Copyright ©2016 John Wiley & Sons, Inc. 23 Let’s Practice! (3 of 6) Which of the following is a homogeneous mixture? a. carbon dioxide b. mercury c. maple syrup d. concrete e. Italian salad dressing Copyright ©2016 John Wiley & Sons, Inc. 24 Let’s Practice! (4 of 6) Which of the following is a homogeneous mixture? a. carbon dioxide b. mercury c. Answer: maple syrup d. concrete e. Italian salad dressing Copyright ©2016 John Wiley & Sons, Inc. 25 Let’s Practice! (5 of 6) Filtration is a common method to separate components of what type of mixture? a. homogeneous mixture of 2 liquids b. heterogeneous mixture of 2 liquids c. heterogeneous mixture of solid in liquid d. homogeneous mixture of solid in liquid Copyright ©2016 John Wiley & Sons, Inc. 26 Let’s Practice! (6 of 6) Filtration is a common method to separate components of what type of mixture? a. homogeneous mixture of 2 liquids b. heterogeneous mixture of 2 liquids c. Answer: heterogeneous mixture of solid in liquid d. homogeneous mixture of solid in liquid Copyright ©2016 John Wiley & Sons, Inc. 27 Copyright Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Reproduction or translation of this work beyond that permitted in Section 117 of the 1976 United States Act without the express written permission of the copyright owner is unlawful. Request for further information should be addressed to the Permissions Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for distribution or resale. The Publisher assumes no responsibility for errors, omissions, or damages, caused by the use of these programs or from the use of the information contained herein. Copyright ©2016 John Wiley & Sons, Inc. 28 1.2 A Scientific Approach to Problem Solving Scientists use a logical process to explain the world around them. This process is called the Scientific Method. Copyright ©2016 John Wiley & Sons, Inc. 29 The Scientific Method (1 of 2) 1. Collect the facts and data relevant to your question. Perform an experiment, then analyze the resulting data to look for trends that relate to the question. 2. Formulate a hypothesis. A hypothesis is a tentative explanation of the data that requires further experimentation to be validated. 3. Plan and perform additional experiments to test the hypothesis. 4. Modify the hypothesis. A useful hypothesis must explain all of the data. Copyright ©2016 John Wiley & Sons, Inc. 30 The Scientific Method (2 of 2) A well-established hypothesis is often called a theory. A theory summarizes a hypothesis that has been supported by repeated experimentation. A theory is valid as long as there is no evidence to disprove it. A scientific law is a statement of natural phenomenon where no exceptions are known under the given conditions. Copyright ©2016 John Wiley & Sons, Inc. 31