WEEK 1: (LESSON 1) THE CHEMICAL WORLD, MEASUREMENT & PROBLEM SOLVING, AND MATTER & ENERGY Lesson Overview
In this Lesson, an understanding of the history of chemical investigation is presented. It is hoped that this will help the student understand the history of experimentation and scientific inquiry such that he or she feels a real-world association with the material to be covered later in the course. A few examples that the student may be familiar with are presented. This Lesson also introduces the student to a cornerstone of the chemical sciences, the manipulation of numbers, and their associated units. These concepts are very important for the rest of the course, and in order to be successful in this course, students must understand them well. Simple and complex unit conversions as well as problem solving strategies will be covered and explained in detail. Finally, the universe is made up of a finite amount of matter and energy. It is these two concepts that tie most chemical principles together. Therefore, we must have a very good understanding of these ideas to develop the more detailed topics later in the course. Temperature, states and properties of matter, and the associated calculations will be covered.
In the laboratory component of this Lesson, the importance of Laboratory Safety is discussed, as well as the importance of knowing the location of safety equipment in the laboratory. Students will also observe differences in density due to temperature.
Students will be able to:
- Demonstrate a basic knowledge of the principles, history, and terminology of general chemistry.
- Recognize the importance of the scientific method in the historical development of chemical knowledge.
- Apply concepts of scientific measurement and problem solving strategies.
- Distinguish between matter and energy.
- Categorize matter and its properties.
In this lesson, we will discuss:
- Chemical problem solving using examples of your choice from the chapters in this Lesson
- Current topics, research, and applications in chemistry and their implications
- Peer-to-peer learning and teaching for understanding of the chemical concepts from this Lesson
Key Learning Concept 1: The History and Basics of Chemistry
- The Scientific Method
- Matter versus Energy
Key Learning Concept 2: The Math of Chemistry
- Unit Conversions
- Significant Figures in Calculations
Key Learning Concept 3: The Characteristics, Differences, and Basic Properties of Matter and Energy
- States and Composition of Matter
- Physical and Chemical Properties
- Conservation of Mass
The following activities and assessments need to be completed for this Lesson:
- Chapter 1 – The Chemical World
- Chapter 2 – Measurement and Problem Solving
- Chapter 3 – Matter and Energy
- Academic Honor Pledge
- Laboratory Assignment 1
- Introduction Forum, Lesson 1 Forum
- Lesson 1 Quiz
WEEK 1: (LESSON 1) THE CHEMICAL WORLD, MEASUREMENT & PROBLEM SOLVING, AND MATTER & ENERGY Reading & Resources
Required Reading with Mapped Course Objectives (CO’s):
Introductory Chemistry, 5th edition, by Nivaldo Tro
Upper Saddle River, NJ: Pearson/Prentice Hall, 2015
- Chapter 1 – The Chemical World (CO-1, CO-2)
- Chapter 2 – Measurement and Problem Solving (CO-3)
- Chapter 3 – Matter and Energy (CO-4, CO-5)
Online Instructional, Demonstration, and Laboratory Videos
Access Code: check your email
- For Chapter 1: 1.1.1 An Introduction to Chemistry
- For Chapter 2: 1.3.2 Significant Figures, 1.3.3 Dimensional Analysis
- For Chapter 3: 1.2.2 Properties of Matter, 1.3.1 The Measurement of Matter
Chapter PowerPoint Files:
Use these slides to help focus your studies on the main points of each chapter. They are also useful templates for note-taking. If you do not have Microsoft PowerPoint, here are directions for installing a viewer to see the slides.
Lecture Outlines and Skill Builder Answers:
Use these Lecture Outlines to help take notes. They also contain answers to the Skill Builder questions that you answer throughout the chapter as you read.
Use these documents for unit conversion values, and to help with naming and formulas of polyatomic ions and acids, prefixes, and transition metal charges.You may want to print these out, since they will continue to be useful throughout the course.
Study key terms from the Lesson on your desktop or mobile device by using these flashcards. It is very important that you familiarize yourself with these terms each Lesson, and that you review terms from previous Lessons!
Please also see this document for instructions on how to register for Study Blue (it’s free). You can then access more flash cards for this class by clicking here: Flash Cards! These are flash cards to help you practice learning the elements, polyatomic ions, acids, naming prefixes, and metric prefixes. You should review these flash cards as frequently as possible, as you must have a working knowledge of this information in order to succeed in this course.
Watch and listen to videos of some of the example problems from each chapter in the text being solved. The narrator will take you step by step through some of the problems. Transcripts are available by clicking on the CC link that accompanies each video.
More Chemistry Videos
Practice Homework Problems:
After you have read the chapters and other resources, taken notes, and watched the lectures, in addition to working through the practice questions, problems, and exercises presented throughout the chapter, you will also find questions and problems and the end of every chapter. The answers to the odd numbered questions and problems can be found in the Answers section in the back of your text. Please be sure to complete these odd-numbered problems so you can help identify those areas on which you may need to focus more. These problems are great practice for the Lesson quizzes, as well as for the midterm and final exam. You need not worry about the sections titled â€œCumulative Problemsâ€ or â€œHighlight Problemsâ€ unless you really want to take on the challenge, or unless you select at Cumulative Problem for your Discussion Forum Topic.
NOTE: These end-of-chapter questions/problems will not be graded. They are for practice only. However, they should be taken very seriously in order to adequately prepare for the quizzes and exams.
Chapter Practice Quizzes:
Please complete these practice quizzes after you read each chapter to help assess your learning of the chapter material. If you do not have Microsoft PowerPoint, here are directions for installing a viewer to see the quizzes.
NOTE: Practice quizzes and exercises will not be graded. They are for practice only. However, they should be taken very seriously in order to adequately prepare for the quizzes and exams.
The APUS Library has put together an online SCIN 131 course guide where you can find more links to online learning tools, texts, scholarly articles, chemical literature, etc. You can find it at the following web address: http://apus.campusguides.com/scin131
In addition, you may find the following websites useful:
Website: WebElements Interactice Periodic Table
Website: Periodic Table of Videos
Website: Chemistry Video Lectures from MIT
Website: Khan Academy Chemistry Videos
WEEK 1: (LESSON 1) THE CHEMICAL WORLD, MEASUREMENT & PROBLEM SOLVING, AND MATTER & ENERGY Lesson
Part 1: The Science of Chemistry, Measurement, Problem Solving, and Matter
So, What is Chemistry, and Why Does It â€œMatterâ€?
â€œThe most incomprehensible thing about the universe is that it is comprehensible.â€
â€”Albert Einstein (1879-1955)
(image credit: www.mentalfloss.com)
So, what is chemistry? What do chemists do? Science is a way of merely looking at and trying to understand the natural world that surrounds us. Have you ever wondered why you need oxygen to survive? Why, when you throw a match into a puddle of gasoline, does it burst into flames? Why, when you mixed together baking soda and vinegar in elementary school to make a volcano, it â€œeruptedâ€? One particular branch of science, chemistry, seeks to answer questions related to all of these examples, and more. Chemistry is the study of matter [anything that has mass and takes up space, thus it is pretty much everything that â€œisâ€]â€”what it is, and how it interacts with itself to produce all the things that exist in our universe.
Chemists, then, are scientists who study matter, the basic building blocks of which are atoms and molecules. Atoms and molecules behave a certain and predictable way, and they possess certain properties that govern this behavior, and thatâ€™s what you will be studying. So, in chemistry, you focus on these atoms and molecules in an effort to understand the properties of the matter that they compose.
Click on image to watch video _x000D_ (Transcript available by following Youtube link)
The Scientific Method
The way that chemists, as well as all scientists, approach such study and investigate our natural world is via an approach known as the scientific method. In its simplest form, this method begins with some sort of observation that leads to a question. For example, you notice that a tree limb burns when placed on a fire, but a metal coin does not. Why? You then formulate a hypothesis (a tentative explanation) about what youâ€™ve observed or a problem youâ€™ve noticed. For example, do only items made of wood burn, and not items made of metal? A hypothesis might then be that anything made of wood will burn on a fire, while anything made of metal will not. Then, you may devise a test or experiment for this question or hypothesis. You may take several samples of different types of wood and several samples of metal items and place them on a fire to see if they burn. You would then record and analyze your data, and draw conclusions or formulate a model that explains the results you obtained, and ultimately, answer your starting question.
If you or others make a lot of similarly related observations, you may be able to summarize them all in the form a scientific law. If one or more similar hypotheses stand the test of time and become firmly accepted amongst scientists, they may lead to the development of a scientific theory. Hypotheses, laws, and theories result in the ability to make testable predictionsâ€”testable via experimentation. Such tests require very controlled procedures that ultimately yield new and important observations. If such predictions are not verifiable, or if they cannot be confirmed, the model (theory), hypothesis, or law must be modified accordingly. It is thus a dynamic, self-updating way of understanding the universe.
Law. A scientific law is a generalization or statement that describes some aspect of the universe, and that seems to always apply under the same conditions in a causal relationship.
Theory. A scientific theory is a model that describes or explains the reasons behind certain observations and laws. A scientific theory is not to be taken lightlyâ€”it is not just a â€œguessâ€ or an idea as would be implied by the use of the term in the general public. In science, a theory carries a lot of evidence-based weight, and offers a very strong explanation for the phenomena it explains.
Units of Measurement
When measuring all of these observations related to matter, scientists use the International System of Units (SI), which is based on the metric system (i.e. meters, kilograms, centimeters, etc.). Actually, the U.S. is the only developed country in the world that does not use the metric system in everyday life; though our scientists use SI units, our citizens still use the English system of measurement (inches, yards, pounds, etc.). But you must use the SI system to solve chemical problems and perform dimensional analysis. Dimensional analysis involves using equivalencies to perform such operations as conversions, predictions, etc. The base units for the SI system include the meter (m) for length, Kelvin (K) for temperature, second (s) for time, and kilogram (kg) for mass. We can combine these units with other units to derive other commonly used units of measurement of which you may have heard: cubic centimeters (cc or cm3) or cubic meters (m3) to measure volume, grams along with cubic centimeters to measure mass and density (g/cm3), and many others. But when we actually measure amounts with laboratory instrumentation, we can never achieve a perfect value because of the inherent limitations of the tools with which we are working. So, when we report our measured values, we do so in way that reflects our measurement uncertainty. We adjust the number of digits accordingly, and any digits that we use when reporting our measurements that are not simply holding place are termed â€œsignificantâ€ figures.
(image credit: Education-Portal.com)
Types of Matter
The matter that we study in chemistry can exists in different states, i.e. solid, liquid, and gas. The difference here has mostly to do with the space between molecules and the amount of energy they possess in each case. It can also exist in different compositions, i.e. pure substances and mixtures. If it is a pure substance, it can be an element, which is a form of matter that cannot be broken down any further into simpler forms of matter. In other words, itâ€™s the simplest form of matter possible. A compound, on the other hand, is matter that is composed of two or more elements, but in fixed proportions. For example, a block of solid aluminum (Al) is elemental matter. However, a block of table salt (NaClâ€”sodium chloride) is a compound, because it is made of at least two different elements (sodium and chlorine), and the proportion is always a 1:1 ratio (1 sodium atom present for every 1 chlorine atom present). But it is still a pure substance so long as no other elements are present in any other combinations or proportions. A mixture, however can be separated further into its componentsâ€”it is not in its simplest form. It can be a homogenous mixture, in which it has the same composition throughout (i.e. salt water), or it can be a heterogenous mixture, in which different regions of the sample will have different composition of its components (i.e. rocky road ice creamâ€”some bites will have more marshmallow than others). This can be summarized in this flowchart.
Properties of Matter and Energy
The properties that matter possesses (that explain the way different samples of matter behave) can be either chemical or physical in nature. For example, gasoline is flammable. That is a chemical property, since it is a reaction with oxygen that releases energy and heat. It results in a rearrangement of atoms to form a different form of matter that wasnâ€™t there before, in this case carbon dioxide and water (a chemical change). Sulfur is a very brittle solid. Brittleness is a physical property, since broken apart sulfur is still sulfur (a physical change)â€”the atoms have not rearranged themselves to express a new form of matter. In other words, it has not changed its composition. Another very important phenomenon influences matter, though it is not mater itself. Energy [Energy is the capacity to do work. Work, then, is when a force is applied over a given distance] can influence changes in matter, and in physical and chemical changes, energy is often exchanged with the surroundings. But it is important to keep in mind that energy is never actually created or destroyedâ€”it merely changes form. This is known as the Law of Conservation of Energy. When something changes into something else, all the energy can be accounted for, and it doesnâ€™t appear or disappearâ€”it merely becomes incorporated within another process. All systems in the universe tend to move from a system of higher potential energy toward a system of lower potential energy, which often results in the release of energy into the surroundings. Itâ€™s like a ballâ€”it will always roll downhill, and never uphill. Energy always works the same way and will follow the path of least resistance.
Chemical Property. A chemical property of a substance is a property that is displayed only when the substance changes its composition through a chemical change. An example is the flammability of gasoline.
Chemical Change. A chemical change is one that results from a rearrangement of atoms in matter. The original substance becomes a different substance, such as rusting:
(image credit: Pearson)
Physical Property. A physical property of a substance is a property that is displayed without a substance changing its composition. An example is the smell of gasoline:
Physical Change. A physical change is one that results in a change of state (i.e. liquid to gas) but not a change in composition (no rearrangement of atoms to become a new substance):
(image credit: Pearson)
Energy. The total energy is the sum of its kinetic energy (energy of motion) and its potential energy (energy of position or composition). Kinetic energy can be transformed into thermal energy, which is the energy associated with temperature:
(image credit: Pearson)
How Is It Relevant to You?
So, how is any of this relevant to your life? Everything is made of matterâ€”you, the technology on which you are reading these words, the air you are breathing. If you can understand matter, you can better control it and interact with your environment in a more productive way to, for example, develop more and better medicines and technologies to increase the quality of life, develop better fuel and power sources, and myriad other applications. Chemistry helps understand why and under what circumstances reactions occur, why some substances exist as a liquid while others exist as a gas, and many other natural phenomena. Communication of findings is important, and it is extremely important that everyone understands one anotherâ€™s claims and values, as well as any uncertainty associated with the values due to how the values were measured. Thus, accurate and precise measurement is paramount, and the degree of measurement reliability must be understood, so that others can evaluate the degree of certainty associated with the claims being made. Furthermore, unless a universal an international system of units is agreed upon and used, numbers become meaningless and confusing when many people begin communicating about the same topic. But to advance all of this knowledge, we have to operate through a logical and sequential system of thought, such as the scientific method. Once people started observing and understanding the world through this approach, knowledge began to grow exponentially. Just think about your own daily lifeâ€¦how much has it changed in the last 5-10 years as a result of science and its resulting technology? Finally, and perhaps more importantly, the more we understand how the universe works and is structured at the atomic level, the deeper the appreciation we can have