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hello im currently taking online chemistry classes on platoweb, i

have evrything done but the final exam and thses offline activities (the documents attached) im also taking other classes that i have to finish and i simply dont have the time to do them

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© 2013 EDMENTUM, INC. Unit 3: Chemical Bonding This Unit Activity will help you meet these educational goals: Science Inquiry— You will do online research, collect information, and analyze it. You will communicate your results in tabular and written form. STEM— You will use simulations and online research to understand scientific reasoning. You will get an insight into STEM careers that are uniquely and personally creative. 21 st Century Skills— You will employ online tools for research and analysis. Introduction Since the 1970s, there’s been increasing public debate about greenhouse gases and global warming. Is the Earth really on a warming trend or is it random variation? And even if the Earth is warming, is it a natural process or is it caused by human activity? And if there is warming caused by human activity, how critical is it, and what’s a reasonable way to deal with it? What’s not in dispute is that greenhouse gases exist and that they are observed to allow visible light to pass through, but absorb and reemit infrared radiation. On a planetary scale, this means that they allow the sun’s light energy to enter the atmosphere, then they retain some of that energy in the atmosphere in the form of heat. That’s generally a good thing, preventing wild temperature swings on Earth between night and day. A change in the Earth’s greenhouse effect, however, would mean a change in the Earth’s climate over time. That wouldn’t necessarily be a good thing. In this unit activity, you will explore more about greenhouse gases on a molecular level. You will use interactive molecular models of some key gases in the atmosphere to find out what structural features differentiate greenhouse gases from other gases in air. You will also research the various viewpoints regarding global warming and explain your views about them. __________________________________________________________________________ Directions and Analysis Task 1: Greenhouse Effect and Global Warming Read the basics about the greenhouse effect , then search the Internet for other authoritative sources to answer the following scientific questions about this phenomenon. Key search terms: greenhouse effect, greenhouse gases, global warming 1 Chemistry Unit Activity
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1. Describe what the greenhouse effect is and how it is caused on a molecular level. Type your response here: 2. How is the greenhouse effect related to global warming? Type your response here: 3. List four greenhouse gases in the atmosphere. For each gas, describe its prevalence in the atmosphere, its natural sources, its human-induced sources, and how its concentration in the atmosphere might be changing. Type your response here: Task 2: Molecular Models of Greenhouse Gases Oxygen, carbon dioxide, and methane are present naturally in the atmosphere. While carbon dioxide and methane are greenhouse gases, oxygen is not. Why not? To find the answer, go to the Cool Molecules Explore site. On the top menu, click entry level to reduce the total number of compounds. On the left pane, click bonds . On the periodic table, select molecules by clicking the individual atoms that form them (the molecules). For example, to select an oxygen (O 2 ) molecule, perform the following: a. Click O , wait for a few seconds, and then click O again. b. Scroll below to see the list of molecules the O-O bond form. Locate the O 2 (g) molecule and click view . c. Below the molecular structure, a drop-down list contains the types of vibrations that the molecule and its bonds undergo. In the “show vibration” box, select each available vibration mode. Observe the way the atoms and bonds move for each mode. d. Answer question 1 below. Note: Sometimes when you select several vibration animations in a row (especially when you select the animations very fast), the simulation seems to lose track and stops. Just close the window and click view for the molecule again to continue. 1. Name oxygen’s only vibration mode and briefly describe its vibrational motion. Type your response here: 2
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© 2013 EDMENTUM, INC. Unit 4: The Mole Concept This Unit Activity will help you meet these educational goals: STEM— You will use online research to understand scientific reasoning. You will get an insight into STEM careers that are uniquely and personally creative. You will use mathematics to solve real world scientific problems. 21 st Century Skills— You will employ online tools for research and analysis, and you will communicate in written form. Introduction In 1811, Amedeo Avogadro proposed that equal volumes of gases at the same temperature and pressure contain the same number of molecules, regardless of their chemical nature and physical properties. This came to be known as the Avogadro hypothesis. This hypothesis went on to become the basis of one of the most widely used constants in chemical measurements, the Avogadro’s number. The Avogadro number and the mole concept are essential tools in chemical research, experiments, and understanding. You can find the composition and formulas of unknown substances and analyze their properties with the help of molar quantities. In this activity, you will explore the history of the Avogadro number and the mole concept and analyze the relationship between them. You will also help solve a hypothetical murder mystery by finding the formula and properties of an unknown substance found at a crime scene. __________________________________________________________________________ Directions and Analysis Task 1: Avogadro’s number and the mole Read about the history of Avogadro’s number and the mole . Then, answer the following questions. You can type the key search terms below to find more about this topic. Key search terms: Avogadro’s number, the mole unit, history of mole 1. Write a short historical account of the discovery of the Avogadro number. In this account, include the roles of Gay-Lussac, Avogadro, Cannizzaro, and Perrin. Type your response here: 2. What is the Loschmidt’s number? How is it related to Avogadro’s number? 1 Chemistry Unit Activity
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Type your response here: 3. The mole and Avogadro’s number are now almost synonymous with each other. We say that one mole of a substance is the amount that contains Avogadro’s number of particles. However, both concepts were developed independently at different times. Analyze the theories and definition of both these concepts. Then, explain why it is correct to define a mole in terms of Avogadro’s number and vice versa. Type your response here: Task 2: The mystery of the unknown substance A prominent automotive businessman has been murdered in New York. The Crime Scene Investigation (CSI) team finds a bottle with some clear liquid at the scene of the crime. The label on the bottle has fallen off. The detectives believe that this bottle belongs to the killer, who dropped it there in a hurry to get away. Their suspects include the victim’s business rival, his lawyer, and a theatre actress. The detectives think that if the CSI team can identify the liquid, they might be able to narrow down the suspects. One of the CSI technicians has analyzed the liquid using a mass spectrometer and found that the compound has a molar mass of 58.0714 g. Further analysis has also revealed that the compound consists of 18 g of carbon, 3 g of hydrogen, and 8 g of oxygen. Now, help the CSI team nab the killer. Answer the following questions to find the identity of the unknown substance. 1. What is the percent composition of all the components in the liquid? Type your response here: 2. What is the empirical formula of the compound? Type your response here: 3. What is the molecular formula of the unknown liquid? Type your response here: 2
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© 2013 EDMENTUM, INC. Unit 5: Chemical Reactions This Unit Activity will help you meet these educational goals: STEM— You will carry out online research to understand scientific reasoning. You will use mathematics to solve real-world design problems. 21 st Century Skills— You will employ online tools for research and analysis. You will communicate using data tables and written explanations. Introduction Fireworks! The lights, colors, patterns, and sounds they create in the night sky are always fun to experience. But, have you ever stopped to wonder how these fireworks work? How do they travel up to the sky and then burst into so many different colors? Well, that’s the magic of Chemistry! Fireworks were invented around A.D. 1000 by the Chinese. In fact, the basic chemicals used in a firework haven’t changed much since then. What has evolved and developed into an art is the way pyrotechnicians use different chemicals to generate amazing effects when a firework explodes. In this lesson activity, you will explore more about fireworks and how they work. You will explore the composition of a firework and find out some of the chemical reactions that occur in them. __________________________________________________________________________ Directions and Analysis Task 1: Chemical reactions in fireworks Read about the components of a firework and answer the following questions. Then type the key words chemical reactions in fireworks in your search engine to learn more about the chemical reactions that take place inside a firework. Key search terms: how fireworks work, chemical reactions in fireworks 1. What are the different types of chemicals used in a firework? Type your response here: 2. What role does each type of chemical play in the firework? Type your response here: 1 Chemistry Unit Activity
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3. What is the composition of the black powder in a firework? Type your response here: 4. Complete the following table for the reactions that occur when the black powder is ignited. Type your response here: Name and Formula of Compound Balanced Chemical Equation Type of Reaction Mole Ratios of Reactants to Products 5. What happens when a firework is ignited? Type your response here: 6. How are the different colors and designs generated in a firework? Type your response here: 7. Which chemicals generate the following colors in the fireworks? Type your response here: Red: Blue: Green: Yellow: Purple: Orange: Silver: 2
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© 2013 EDMENTUM, INC. Unit 6: Kinetic Molecular Theory and Gas Laws This Unit Activity will help you meet these educational goals: Science Inquiry— You will learn about the atmosphere by doing online research. You will also use a simulation to make observations and analyze results related to the effects of greenhouse gases and other variables on the atmosphere. You will communicate your results in written form. 21 st Century Skills—You will employ online tools for research and analysis. Introduction The eastern half of the United States is highly urbanized and industrialized. As a consequence, most of the lakes and streams in this region are acidified. According to the National Surface Water Survey, about 14% of the lakes in the Adirondack Mountains in New York and about 12% of streams in the mid-Atlantic Highlands have high acidity levels in their water and are chronically acidic. This phenomenon is not restricted to the United States. According to an estimate from the Canadian government, about 14,000 lakes in eastern Canada are also acidic. Worldwide, our atmosphere is affected by a host of gasses that are released through natural events or through human activity. The burning of fossil fuels, such as diesel, gasoline, and coal, release nitrogen and sulfur oxides into the atmosphere, contributing to acid rain. Combustion of fossil fuels also contributes to the greenhouse gases in the atmosphere. How might everyday human activity affect our Earth and the diversity and quality of life here? To begin to find some answers, you first need to know about the layers and composition of the Earth’s atmosphere and how it supports life on Earth. Then, you need to understand a bit more about the mechanics of greenhouse gases and the complex interactions. Both subjects are based on a deep understanding of kinetic molecular theory and the behavior of gasses. __________________________________________________________________________ Directions and Analysis Task 1: Earth and Its Atmosphere Earth’s atmosphere works like a shield. Without this shield, our planet would be about 33 degrees Celsius warmer than it is now and would not be able to support life! The atmosphere blocks most of the harmful rays from the sun and traps heat within so that our days are not too hot and nights are not too cold. Read about Earth and its atmosphere and use the key search terms to find more information. Then answer the questions below. Key search terms: Earth, atmosphere, layers of atmosphere 1 Chemistry Unit Activity
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1. What is the composition and percentage of the gases in Earth’s atmosphere? Type your response here: 2. List in ascending order the different layers of atmosphere, their heights, and main features. Type your response here: 3. Why are the gases in the troposphere layer denser than the gases in the other layers? Give reasons for your answer. Type your response here: 4. How does the kinetic theory of gases explain the weather changes happening in the troposphere ? You can also research on the Internet using keywords such as troposphere , atmospheric layers , and weather changes . Type your response here: 2
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