Chemistry lab report help

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I need help writing a lab report for my general chemistry class. I have attached my data as well as my outline for the lab I followed. I do not have any background info for this lab. I have attached the format of how to write the report as well as my data. The lab document will help with background if needed.

Lab 12 data The following balanced equation describes the chemical reaction that took place. NaHCO3 (s) + HC2H3O2 (aq)  NaC2H3O2 (aq) + CO2 (g) + H2O (l) *Molar ratio for each product and reactant from balanced equation for chemical reaction is 1:1* Estimated total volume of quart sized Ziploc bag by filling with water until overflowing and shutting so that no air was inside, then measuring fluid using 1oo-mL graduated cylinder Measured volume: 1190 mL Volume of CO2 gas required to completely inflate bag is equal to measured fluid amount (1.190 L) Calculations to determine moles of CO2 gas: (using STP standard molar volume of 24.465 L/mol @25*C and 1 atm) 1.190 L CO2 / 24.465 L = 0.04864 moles CO2 Determine grams of NaHCO3 solid: 0.04864 moles NaHCO3 x 83.978 grams NaHCO3 (per 1 mole) = 4.085 g NaHCO3 Determine mL of 6 M HC2H3O2 aqueous: 0.04864 moles HC2H302 / 6 Moles (per Liter) = 0.008107 L 0.008107 L x 1000 (mL/L) = 8.107 mL (6M HC2H3O2) Measured amounts placed in clean dry bag: 4.098 g NaHCO3 (s) 8.12 mL 6M HC2H3O2 Reaction proceeded for 30 minutes, with complete inflation of bag at completion of reaction (no more bubbling appearance/fizzing sound). Clear fluid remained at bottom of bag (water and aqueous NaC2H3O2). Claire, I ran three more trials, beginning them before the first trial was completely reacted, and not allowing enough time for them to finish. Because the first trial was accurate, I’m not going to mention the other trials (they weren’t a required part of the lab). So I’m going to use the above stoichiometric and ideal gas law calculations to support the assumption that using stoichiometry to determine the necessary amounts of reactants will result in the desired amount of product/s.
Brian McClain ID# 00551495 How to write a formal laboratory report In this course, your experiments will be written up as formal lab reports. The formal lab report must be printed out and turned in at the beginning of lab. A laboratory report consists of the following separate sections: 1. Title 2. Abstract 3. Introduction 4. Experimental 5. Results and Discussion 6. Conclusion 7. References You need to delineate each section of your report with these headings so I can clearly tell the section I am reading. The exception to this is the title. You do not need to put Title before the title of your report; the title should be self-evident to me. Please see the Sample Formal Lab Reports if you have questions about this. ALWAYS WRITE YOUR REPORTS IN THE THIRD PERSON USING PAST TENSE. Examples: Correct – The unknown acid solution was titrated with 0.512M standardized sodium hydroxide dispensed from a burette. Incorrect – We will use 0.5 M NaOH to titrate the unknown acid. 1. The Title of your report should be at the top of the first page, and be a one-line summary of what the experiment was about. For most of these experiments, you can simply copy the title from the procedure given to you. Example: Determination of the concentration of an unknown acid 2. An abstract is one of the most important parts of a formal lab report. It is a short summary of the purpose and outcomes of the experiment. It should be direct and to the point. It should be no more that 300 words. It should clearly state the purpose of your report and include your final results with error and any literature or theoretical results as well. It should NOT include a description of the experiment or a discussion of the results. It should be the last thing you write when constructing your formal lab report. The key is to plan your argument in a series of sentences, and then use these to structure the entire report. 1. State the problem you tackle. What’s the key purpose? Again, in one sentence. If you can’t summarize your report in one key question, then you don’t yet understand what you’re trying to write about. Keep working at this step until you have a single, concise (and understandable) sentence. 2. Explain, in one sentence, how you tackled the research question. 3. Briefly, in a few sentences, what were the most pertinent experiment(s) you performed to get your objective? What were the results? Be sure to include any error in your results. How do your results compare to literature or theoretically calculated values? Be sure to include the proper units with your reported results. 1 Last Revision: 12/16/15 bmc Brian McClain ID# 00551495 Remember, the word ‘abstract’ means a summary of the main ideas with most of the detail left out. So feel free to omit detail. Example: Absorbance spectroscopy was used to measure the formation of a charge transfer peak between mesitylene and iodine in pentane. Beer’s Law was used to measure changes in the absorption peak. This allowed the determination of the binding energy of an electron transferred from mesitylene to iodine. The maximum absorption wavelength for the charge transfer complex was found to be at 327(± 5) nm. This resulted in a binding energy for the excited state complex of 5.34(± 0.01) eV. The literature values for the electron affinity of iodine at 298K and the ionization energy of mesitylene at 298K are reported as 5.059 eV and 8.40 eV, respectively. The molar absorptivity and equilibrium constant for the activated complex were determined to be 8440(±20) M-1cm-1 and 1.4( ± 0.4) x 10-4, respectively. 3. The Introduction section should give a general description of what you were trying to do in the experiment. It is meant to give the reader an idea of what you were trying to show and how you were doing it. The introduction makes it very clear to the reader why the experiment was undertaken, the relevance of the experiment, and reasons for its importance. Why is the experiment being performed? It is imperative to include all necessary chemical equations in the introduction. Cite references that SUPPORT your work in the introduction. DO NOT cite a reference as a quotation like in a news article. You reference the work done by others in your own words, summarizing how your work supports or refutes their conclusions, then you reference that work (see proper citation methods at the end of this document). The introduction should discuss alternative techniques and provide justification for why the specific technique was chosen. You must cite a reference with a real world example of an application that tests the theory in question and how it was applied. Your textbook is not a valid reference source; you must use a scholarly journal as your reference citation. Example Citation: The method of selective precipitation is used heavily in the mining industry to separate out metals from their ores. Colbert et al have developed a process based on the addition of sulfates to separate barium from magnesium rich deposits [2]. Things to discuss include what theory or model (an equation perhaps) is being tested and how the desired quantity being investigated will be extracted from the data. In other words, how can the model be used to measure the property under investigation? You must also discuss what assumptions are incorporated in the theory and how those assumptions will be tested. Any assumptions that are made in the experiment or implicit in the model/theory being tested must be stated clearly. Example Assumption: Gas pressures were measured at 25 oC and used to to determine the Ideal Gas Constant. It is assumed that under the current experimental conditions the gases do not interact and behave ideally. If you do not understand what theory is being applied or tested in the experiment you will do very poorly on your report. It is important that you are very clear what the theory under investigation is before you begin writing your report. 4. The Experimental section should provide the reader with enough information that they can understand what you did, and if necessary, repeat your experiment. IT SHOULD BE BRIEF! You can assume that someone reading your report will have the same skillset as you and thus use appropriate language to describe your methods. The Experimental Section should summarize what you OBSERVED when following the procedures. This section needs to be concisely written, but make sure that all the important information is included. DO NOT restate the 2 Last Revision: 12/16/15 bmc Brian McClain ID# 00551495 procedures in the lab; only discuss the observations that were made and any modifications to the procedure. The actual procedure must be cited. DO NOT include your experimental data in this section. You should include how calibrations were performed, the actual concentration of reagents used, and any other information that may differ from the written procedure. Example: The 0.1002 M solutions were mixed in a 12-well well plate rather than in test tubes as directed in the written procedures. After mixing solution A with solution B the resulting solution turned red. This experiment was performed according to the procedures as provided in the CHEM111 laboratory manual [3]. For most of your reports, you will be following the procedures that are given to you. You have to fully detail the source, including authors/title/edition/publisher/year/page numbers! See methods of referencing at the end of this document. 5. The Results and Discussion section is the “meat” of your report, where you summarize the data you determined in your experiment, and discuss what it means. The Results and Discussion section should include a detailed EXPLANATION OF WHAT WAS OBSERVED. It will NOT be brief. Observations that are important need to be included, for example, if your solution turned blue when you added ammonia to your aqueous solution – which implies that there was copper in your unknown sample – you need to state this. You need to include important changes like precipitates forming, temperature changes, color changes in solutions, etc. and what these findings imply! This is different from the experimental section where you just state your observations without discussing how those observations affect your results. At all times when discussing your observations you need to include balanced chemical equations or refer to the chemical equation(s) listed in the Introduction Section. Example: The red color appearing in the solution that resulted from the mixing of solution A and solution B is due to a shift in the equilibrium towards products. This is related to Le Chatlier's principle whereby the reaction restores equilibrium after the additional of A, a reactant, is added to the solution by producing more products. Results should be summarized into Tables and Graphs wherever possible, with appropriate captions describing what they represent. Remember that captions should be put above Tables and below Figures. All Tables and Figures must be numbered in sequential order. If you have results that must be calculated from an equation, give one “typical” example of your calculations, and summarize the other final values in a Table. Graphs should be made using XY-scatter plots WITHOUT connecting lines between the points. Any lines on the graph should be trendline fits and have the trendline equation displayed on the graph or the equation stated explicitly in the figure caption. If your experimental value has previously been measured or a literature value is available, you should compare these data to your value using a percent difference calculation. You have to properly reference any literature that you include in your report; these references should be in numerical order at the end of your report (after Conclusions). If your determined value is different from the literature, you need to provide a reasonable discussion of what may have caused the difference. Experimenter error is NOT a sufficient answer. You should especially discuss potential errors that might have influenced your measurements, and give an idea of how accurate your experimental value is. Remember to use correct significant figures when reporting data and final values! If a literature value isn’t available for comparison, and you ran a minimum of three trials of the experiment, you should report the 95% confidence level for your experimental value. 3 Last Revision: 12/16/15 bmc Brian McClain ID# 00551495 Each Results and Discussion section will be different, but remember – you are explaining what you found, and what it means, to another scientist. You need to be concise, but include all important information. 6. Conclusion. A summary of what you found in this laboratory exercise. Should be no more than four to five sentences stating the major finding of the report. In addition, the validity of the assumptions made in the experiment must be addressed. Example: From the decomposition of calcium carbonate in a closed system at 800K the experimental gas constant was found to be 8.31(±0.05) J K-1 mol-1. The gas generated in the reaction was CO2 and, as evidenced by the close agreement of the experimental gas constant and the accepted value for the ideal gas constant, we can conclude that the assumption that CO2 behaves ideally is valid under the experimental conditions used. Thus, the Ideal Gas Law is an appropriate model to use for decomposition reactions at high temperature. 7. References: Be consistent with your style of literature citations – as chemists we use the American Chemical Society style (see below). The way to do this is to include the references in the Reference section at the end of the report. Then you cite this reference as you are writing up the report. Within the body of the paper give name(s) and year published for one or two of the author citations. If more than two authors wrote the paper, give the name of the first author followed by et al. and the year published. In the References section, be sure to list all the authors! You need to include a minimum of TWO references. One should be your lab manual and the other should be from a scientific journal, preferably the source you used in the introduction to support your study. Your textbook is NOT a suitable second reference; though it could be used as a third source. References: 1. Moore, J.W.; Stanitski, C.L.; Jurs, P.C., in Chemistry: The Molecular Science; 2nd Ed.; Publisher: Brooks-Cole, San Francisco, CA, 2006; p. 451. 2. Colbert, S.R.; Jokela, E.J.; Neary, D.G. J. Phys. Chem. 1988, 92, 842. 3. Po, Henry and Senozan, N. “General Chemistry Experiments CHEM111”, 8th Edition, 2004, Hayden-McNeil Publishing, pp 33-40 Within the body of the paper give name(s) and year published for one or two of the author citations. If more than two authors wrote the paper, give the name of the first author followed by et al. and the year published. For example, in the body of your report where you compare your R value to the literature R value you should state something like, “The experimental R value was found to be 0.085(±0.005) L atm mol-1 K-1. This is 4% different from the literature value of 0.0821 L atm mol-1 K-1 as given by Moore et al [1]. The error in the experimental result is within the 95% confidence level.” A good source to see how to cite different types of references is on the ACS website, For a web citation, you should use the following form: Classroom Connect. Citing Internet Resources. [Online] Available, October 3, 1999. So a web citation would look something like, 3. Experiment 1: Determining the Ideal Gas Constant. [Online] Available 4 Last Revision: 12/16/15 bmc Brian McClain ID# 00551495, September 17, 2007 Reports are always written using the 3rd person (for example, you would say “3 drops of ammonia were added” NOT “I added 3 drops of ammonia”) and in the past tense. Always spell- and grammar-check your report before you hand it in! Appendix: All experimental data collected, and long form analyses (i.e. Excel sheets) should be included in an appendix at the end of the report. Formatting: To be consistent your laboratory reports should be written using a word-processing program (Word, GoogleDocs, Pages, etc.). Please use double-spacing and 1 inch margins throughout. Graphs should also be generated by computer (Excel), and copied into the Word document. Chemical formula should be properly written with subscripts (e.g. CH3OH), temperatures should have degree signs (use superscript “o”; e.g. 25 oC). All pages should be sequentially numbered. Your name and ID number should also be on every page as a header and NOT imbedded in the document. See this document for an example. 5 Last Revision: 12/16/15 bmc
CHEM 1111 Lab 14: A CAPSTONE EXPERIENCE: TOWARD THE CREATION OF AN AUTOMOBILE AIRBAG NAME: SECTION: I. Objectives: • Learn how to use stoichiometry for non-STP gases • Clarify the concept of limiting and excess reagents • Synthesize chemical reactions to understand how automobile airbags are created sh is ar stu ed d vi y re aC s o ou urc rs e eH w er as o. co m II. Materials needed: Safety goggles, baking soda, vinegar, sealable plastic bags (sandwich, quart, and halfgallon sizes all work well), graduated cylinders (up to 500 mL or 1 L, if available), spatulas, analytical balance with at least ±0.01 g precision, weighing paper, ample paper towels. III. Background: Include any equations, reactions that are required for this lab Reaction of sodium bicarbonate with acetic acid NaHCO3(s) + CH3COOH(aq) → CH3COONa(aq) + H2O(l) + CO2(g) Th A) Put the reactants in opposite corners of the bag, making sure the components are separated B) mix the reactants together C) This is how the bag should look if you used the correct amount of reactants IV. Safety: • There are no significant hazards in this experiment V. References: All references must be cited, including any websites. (1) Whitmer, J. C. Kitchen Chemistry. J. Chem. Educ. 1975, 52 (10), 665. sh is ar stu ed d vi y re aC s o ou urc rs e eH w er as o. co m (2) Carlson, G. L. A New Approach to the Baking Soda-Vinegar Reaction. J. Chem. Educ. 1990, 67 (7), 597. (3) Ed. Staff.. How Big is the Balloon? Stoichiometry Using Baking Soda and Vinegar. J. Chem. Educ. 1997, 74 (11), 1328A−1328B. (4) Duffy, D. Q.; Shaw, S. A.; Bare, W. D.; Goldsby, K. A. More Chemistry in a Bottle: A Conservation of Mass Activity. J. Chem. Educ. 1995, 72 (8), 734−736. (5) Rohrig, B. Fizzy Drinks: Stoichiometry You Can Taste. J. Chem. Educ. 2000, 77 (12), 1608A−1608B. (6) Antony, E.; Mitchell, L.; Nettenstrom, L. When A + B ≠ B + A. J. Chem. Educ. 2000, 77 (9), 1180−1181. (7) Artdej, R.; Thongpanchang, T. A Dramatic Classroom Demonstration of Limiting Reagent Using the Vinegar and Sodium Hydrogen Carbonate Reaction. J. Chem. Educ. 2008, 85 (10), 1382− 1384. (8) Thorsen, K. Chem 13 News: Ways to Teach in the Classroom and Beyond. J. Chem. Educ. 2000, 77 (7), 824. (9) Criswell, B.; Bennett, C.; Bevsek, H. M. Two “Gas-in-a-Bag” Reactions to Show the Predictive Power of the Relative Acid-Base Strength Chart. J. Chem. Educ. 2006, 83 (8), 1167−1169. (10) Mattson, B.; Hoette, T. Incomplete Combustion of Hydrogen: Trapping a Reaction Intermediate. J. Chem. Educ. 2007, 84 (10), 1668−1670. (11) Lanni, Laura M. "Filling a Plastic Bag with Carbon Dioxide: A Student-Designed Guided-Inquiry Lab for Advanced Placement and College Chemistry Courses." N.p., n.d. Web. 30 Nov. 2016. Th VI. Procedure: 1. Find the capacity of the plastic bag by filling it completely with water and then measuring the volume of the water. The volume of the water will be the same volume of carbon dioxide needed to fill the bag completely. 2. Calculate the temperature of the room in Kelvin. 3. Find the atmospheric pressure. 4. Calculate the amount of vinegar necessary to produce the target volume of carbon dioxide. 5. Find the mass of baking soda needed to produce the target volume of carbon dioxide 6. In order to control the reaction, condense all of the baking soda into a corner of the bag 7. Next add double the amount of vinegar to the other corner of the bag. Make sure the components don't mix 8. Push out all of the air and seal the bag 9. Shake the bag vigorously 10. Make sure the bag isn't “wimpy” or exploded. If so, the reaction failed VII. Data and Analysis: Design a data sheet and analysis section for the lab. Record the mass of water ______ Estimate the mass of carbon dioxide that will be produced ______ Amount of baking soda used ______ Amount of vinegar used ______ Record what you see happening in the bag sh is ar stu ed d vi y re aC s o ou urc rs e eH w er as o. co m VIII. Reflection Questions: In this section you will design a minimum of three questions that you anticipate to test in the lab while performing the experiment. On performing the lab you should be able to answer these questions. 1. What are some sources of error and how could you prevent them? 2. Using the knowledge that you gained from the experiment, explain how an air bag works Th 3. Which of the reactants is the limiting reactant? Powered by TCPDF (

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