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Description Hello, Please complete the lab report template attached using the details from the experiment attached and the graph. Thank you!

Description Laboratory 8 Procedure: Radiation The impact of the radiocarbon dating technique on modern man has made it one of the most significant discoveries of the 20th century. No other scientific method has managed to revolutionize man’s understanding not only of his presentbut also of events that already happened thousands of years ago. Archaeology and other human sciences use radiocarbondating to prove or disprove theories. Over the years, carbon-14 dating has also found applications in geology, hydrology, geophysics, atmospheric science, oceanography, paleoclimatology and even biomedicine. Radiocarbon (carbon-14) is an isotope of the element carbon that is unstable and weakly radioactive. The stable isotopes are carbon-12 and carbon-13. Carbon-14 is continually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen-14 atoms. It is rapidly oxidized in air to form carbon dioxide and enters the global carbon cycle. Plants and animals assimilate carbon-14 from carbon dioxide throughout their lifetimes. When they die, they stopexchanging carbon with the biosphere and their carbon-14 content then starts to decrease at a rate determined by the law of radioactive decay. See the following reference for more information: Team, ESRL Web. “ESRL Global Monitoring Division - Education and Outreach.” NOAA Earth System Research Laboratory, 1 Oct. 2005, www.esrl.noaa.gov/gmd/education/isotopes/decay.html. The number of nuclei disintegrating per unit of time is called the rate of radioactive decay, and can be calculated from the following formula: Rate = k Nt Figure 1. Equation for the rate of radioactive decay, where Nt is the number of radioactive nuclei at the time t, and k is the decay rate constant for radioactive decay or decay constant. Another important term is a half-life of a radioactive nucleus, that is defined as the time it takes for one –half of the nuclei in the sample to decay. The half-life is independent of the amount of the sample. T1/2= 0.693 / k Figure 2. Equation for the half-life of a radioactive nucleus, where k is a decay constant. Figure 3. Example of Radioactive Decay curve. There are couple of objectives of this lab: To enhance your ability to understanding of the radioactive decay and a half-life To familiarize you with the half-life curve. Pre-Lab Questions: Analyze Figure 3. Radioactive Decay curve presented and answer the following questions. What property is listed on x-axis? What time corresponds to the decay of the half of the sample? 2.What property is listed on y-axis? 3.What is the total mass of the sample? 4.What is the mass of the half of the sample? 6.What is the half-life of the sample? Procedure: Read pages 698 –704 of your textbook prior to completing the procedure. Collecting Data – Part I From the course home page, access the simulation environment by clicking on the Radioactive Dating Game. 1.After the simulation environment loads, click on the “Half-Life” Tab. 2.Select carbon-14 from the right menu. 3.Inspect the graph and record its estimated half-time below. 4.Select 10 carbon-14 atoms from the bucket and move them to the white workspace. The goal is to measure how many of them undergo the decay process up until they reach the carbon-14’s half-life. Record the number of atoms that decay prior to the half-life in the table below. (Nt) 5.Repeat your measurements for 20, 30, and 40 atoms. 6.Repeat steps 1-5 for uranium-238. 7.Calculate the average Nt value for each radioactive element and enter the values in the ‘Average’ column in the first table below. 8.Using the equation in Figure 2, calculate the decay constant and enter the values in the table below. 9.Using equation in Figure 1, calculate rate of the radioactive decay and enter the values in the table below. Nt Estimated t1/2 (years) 10 atoms 20 atoms 30 atoms 40 atoms Average Carbon-14 Uranium-238 Decay Constant Rate of Decay Carbon-14 Uranium-238 Collecting Data – Part II 1.Select the “Dating Game” tab at the top of the simulation. For this part of the simulation, you will collect data in an effort to determine the age of various types of matter using carbon dating. The table below contain the samples that will be tested. 2.Click and drag the probe to the ‘Living Tree’ near the animal skull. Notice that a dialog box will pop up once the probe is properly located over the sample. Record the percentage of carbon remaining in the table below. 3.Predict the age of the sample and record this in the table below. Check your answer in the dialog box. 4.Repeat steps 2 and 3 for the remaining samples. 5.Finish the lab by preparing a report. Sample % Carbon Remaining Age of Sample Living Tree Animal Skull Wooden Cup Bone Fish bones Rock 5 Notes This section should include notes about any observations or calculations of data collected during the lab. Report Requirements This section contains key information that must be included in your typed report. Define the problem in a manner that is clear and insightful. Clear hypothesis statement and other potential solutions that identify any relevant contextual factors (i.e. real-world costs). Clearly stated results and discussion of possible improvements to the procedure. Conclusive statements arguing in favor of your findings. 2.Identify the strategies and procedures used during the lab. 4.Clear presentation of data including any tables or other figures that are relevant to understanding your stated conclusions at the end of the report. Include any relevant calculations performed during the lab. Note: All reports will be graded using the rubric embedded within the course. Here are some questions to consider as you write your report: Does my problem statement make sense? Have I summarized my strategies/procedures well enough to be replicated by an outsider? Do my tables and/or graphs make sense? Did I thoroughly summarize my laboratory experience in a concise, factual way such that the reader can understand my processes and findings in the conclusion section alone? 2.Did I have a valid hypothesis at the start of the lab? Have I expressed this in my report? 4.Are my conclusions valid based on my supplied data?

Description All of the directions are in the file I added below. This is the lab. I would prefer if you would print out the lab and directly write onto it and then send me pictures of the lab.

Description 1. In the following reaction:  Fe2O3 + 3C ? 2Fe + 3CO; how many grams of C are needed to react with 16.5 g Fe2O3? 2. Give an example of a physical change and chemical change.   3.  A sample of nitrogen (N2) has a volume of 50.0 L at a pressure of 760 mmHg. What is the volume of the gas when the pressure changes to 1500 mmHg if there is no change in temperature. 4. Calculate the molarity (M) of 4.0 g of KOH in 2.0 L of solution. 5.  Indicate whether the following solutions are acidic, basic or neutral.   a. [H3O+] = 6.0 x 10-12 M   b. [H3O+] = 1.4 x 10-4 M

Description The required textbook is: The Science of Cooking: Understanding the Biology and Chemistry Behind Food and Cooking By Joseph J. Provost, Keri L. Colabroy, Brenda S. Kelly and Mark A. Wallert These are two separate activities :)

Description Question 1 a) Write down the overall equation showing the formation of [Fe(acac)3] from [Fe(H2O)6]3+ and acetylacetone (equation 4.3 in the Introduction). b) What reagent do you weigh out that ends up being the source of the [Fe(H2O)6]3+? Question 2 a) Circle the correct word in bold text to complete the following statements: A pH of less than 7 means a solution is acidic/basic. A pH of greater than 7 means a solution is acidic/basic. b) The equation showing acetylacetone, acacH, forming the acac¯ ion is below: acacH acac¯ + H+ What is it about this equation that results in a solution of acacH being slightly acidic? c) Given that sodium acetate is a base (remember that sodium acetate can be considered as sodium ions and acetate ions), complete the following equation showing the reaction of acetate ions with H+: CH3COO– + H+ Question 3 a) What is the connection between the two equations below? acacH acac¯ + H+ [Fe(H2O)6]3+ + acac¯ [Fe(H2O)4(acac)]2+ + 2H2O b) Using your answer to Question 3(a), explain why the pH of a mixture of [Fe(H2O)6]3+ and acacH (solution 2, Table 4.1) is lower than a solution of either of the components by themselves. c) Explain why the pH increases on addition of sodium acetate (solution 3, Table 4.1) d) Therefore, explain why more [Fe(acac)3] is produced after the addition of sodium acetate. (Hint: use Equation 4.3 and Le Châtelier’s Principle.) Question 4 a) Steps 1 and 2 in the PROCEDURE describe test tubes A and B in Diagram 1. Test tube A should contain the neutral [Fe(acac)3] complex synthesised in Part One and polar water, test tube B should contain [Fe(acac)3] and non-polar dichloromethane. Using the idea of “like dissolves like”, which test tube – A or B – do you predict will contain the dissolved [Fe(acac)3]? (Hint: see the notes on solubility in the Introduction section for help.) b) If the intensity of the colour of the solutions can be taken as a rough guide as to the concentration, which solvent layer in test tube B, the top or the bottom, contains the most [Fe(acac)3]? c) Is the layer you chose in question 4 (b) the polar (water) layer or the non-polar (dichloromethane) layer?

Description Hello there, I need help on my post lab. It is for Elimination experiment.

Description Assignment: Properties [img alt="Iron Thinking Man" src="http://static.k12.com/eli/bb/334/2_23579/1_124929_3_23582/2d68c7fa3ee651e7764b4c0f5caa5a971a4e0d8f/media/8ef0a376b7317f225ffb20c591d122a9f3f627e8/mediaasset_630667_1.jpg" title="Iron Thinking Man">  For each of the objects list six physical properties of the object. Identify each property as extensive (E) or intensive (I) and describe how you know it is an intensive or extensive physical property. Then, select one property you identified for each object and describe, in detail, how you would test that property. For example, if you determined that a metal rod is very dense, how would you measure its density? Record your answers in the template provided and submit them to the Assignment: Properties link for grading. For more information on how this will be graded, please view the grading rubric.

Description I need you answer the questions very carfully! I attached the question in this document if you cant do it dont bid on it please before you read the questions! moudle 2 is related to the excell sheet table

Description Chemistry II Laboratory 3 Procedure – Chemical Equilibrium Background: Chemical equilibrium is dynamic condition that plays an important role in our life since many of food metabolism processes are controlled by equilibrium. A variety of industrial processes are based on the chemical reactions that do not proceed to completion. It is important to know how to manipulate such reactions in order to obtain the maximum amount (yield) of theproduct. Chemical equilibrium can be disturbed by variety of factors: change of regents' concentrations, removal of the products, or change of the temperature, just to name a few. In this lab, we will study the Le Chatelier's Principle through the observation of the effect of disruptions (such as concentration or temperature) applied to the following reaction, by analyzing its color changes: [Co(H2O)6]+2 + 4Cl- ? CoCl4-2 +6H2O Figure 1: [Co(H2O)6]+2 forms a pink complex, and CoCl -2 is a blue complex. Cobalt (II) does not exist in aqueous solution as a free ion, however it forms a pink complex with six water molecules. In the presence of chloride ions, different complex is formed, the blue CoCl4-2. There are few objectives of this lab: 1. To enhance your ability to apply Le Chatelier'sPrinciple. 1. To improve your understanding of the equilibriumconstant. 2. To analyze the responses of the equilibrium constant to the perturbations such as change of concentration ortemperature. Before you start this laboratory assignment, you are encouraged to review Section 14.1-14.3 and 14.6 on page 487 in the textbook. Throughout this laboratory assignment, you will be required to perform and thoroughly document your calculations pertaining to the stoichiometry associated with the reaction above. Be sure to record all observations and any relevant notes that you think you will need to include in your laboratory report. Take a moment to formulate and write down a hypothesis describing how the addition of chloride ions, distilled water and silver nitrate will affect the equilibrium of this reaction? Pre-Lab Questions: 1. State the La Chatelier'sPrinciple. 2. Write the equilibrium constant for the reaction in Figure1.(Note: You are encouraged to use the MS Word equation editorto construct the equilibrium constant for later use in your report.) Procedure: Preparing the Lab I 1. From the course home page, click on the Virtual Lab Tutorial link to watch theoverview of using the virtuallab. 2. From the course home page, access the lab environment by clicking on the Virtual Lab link. 3. After the lab environment loads, click ‘File’ then ‘Load anAssignment.’ 4. Select the 'Chemical Equilibrium' category. 5. Select the 'Cobalt Lab'assignment. 6. At this point, you have access to the first experiment with the required supplies to complete yourexperiments. If you haven’t already done so, formulate a hypothesis about the effect of addition chloride ions, water, and silver nitrate on equilibrium as you will need to include this in your final report. Performing the Experiment 7. Select the 'Glassware' tab in the stockroom. Then, select empty 1000 mL Erlenmeyer flask. 8. Then select the 'Solutions' tab in the stockroom, click on 'Cobalt (II) Chloride Exp Solutions' transfer Erlenmeyer flask containing 1M CoCl2 to theworkbench. 9. Selectthe'Stockroom'then'Solutions'tab,transferErlenmeyerflaskcontaining12MHCl solution to theworkbench. 10. Selectthe'Stockroom'then'Solutions'tab,transferErlenmeyerflaskcontaining6M AgNO3 solution to the workbench 11. Select the 'Stockroom' then 'Solutions' tab, transfer Erlenmeyer flask containing distilled water to theworkbench. 12. Transfer 25 mL of 1 M CoCl2 into the empty 1000mL Erlenmeyer flask by moving flask with CoCl2 and dropping it onto the empty one. We will now collect some data about this solution. 13. Record the values for the concentration (molarity), and the color of the solution. 14. Add 2 mL of concentrated (12 M) HCl to the 1000mL Erlenmeyer flask. Continue until you see a change in equilibriummixture.Record your observations. 15. Continue adding HCl until no further change occurs. Record yourobservations. 16. Add 2 mL of distilled water to the reaction mixture. Continue until a changeoccurs.Record yourobservations. 17. Continue adding water until no further change occurs. Record yourobservations. 18. After you record your data, clear the workbench but do not close the virtuallab! Data Analysis 19. Before completing this lab, you will need to conduct a thorough analysis of your data in order to answer the mandatory questions below. You will need to include yourresponses to these questions in your written report in the appropriate section(s). You can use the virtual lab to investigate answers to thesequestions. a) Imagine the following scenario: a student doing the experiment added 20 mL of silver nitrate, AgNO3, to the blue equilibrium mixture. The reactionmixture become pink and cloudy with white precipitate of silver chloride , AgCl, appearing in the bottom of the flask.Can you explain how those observations are consistent with Le Chatelier's principle? b) Imagine the scenario: A student placed pink equilibrium mixture in the hotwater. Reaction mixture changed color toblue.Is the reaction endothermic or exothermic?How the change of the temperature influences the equilibrium of this reaction? Explain. Notes This section should include notes about any observations or datacollected during the lab. Report Requirements This section contains key information that must be included inyour typed report. 1. Define the problem in a manner that is clear andinsightful. 1. Identify the strategies and procedures used during thelab. 2. Clear hypothesis statement and other potential solutions that identify anyrelevant contextual factors (i.e. real-worldcosts). 3. Clear presentation of data including any tables or other figures that are relevant to understanding your stated conclusions at the end of the report. Include anyrelevant calculations performed during thelab. 4. Clearly stated results and discussion of possible improvements to theprocedure. 5. Conclusive statements arguing in favor of yourfindings. Note: All reports will be graded using the rubric embedded within the course. Here are some questions to consider as you write your report: 1. Does my problem statement makesense? 1. Have I summarized my strategies/procedures well enough to be replicated by anoutsider? 2. Did I have a valid hypothesis at the start of the lab? Have I expressed this in myreport? 3. Do my tables and/or graphs makesense? 4. Are my conclusions valid based on my supplieddata? 5. Did I thoroughly summarize my laboratory experience in a concise, factual way suchthat the reader can understand my processes and findings in the conclusion sectionalone?