UNC-Chapel Hill CHEM 101 - Experiment 5: Gas-Forming Reactions and Rockets

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Experiment 5: Gas-Forming Reactionsand RocketsPost-Lab Results & Data AnalysisEXAMPLE CALCULATIONS (6 pts)Post-Lab Discussion QuestionsAnswer the discussion questions below within the answer boxes provided using 1-3 complete sentences. Where appropriate, refer to the table and figure above and include specific data and analysis as needed.1. In this experiment, one of the two gas-forming reactions uses a catalyst (not a reactant) to significantly increase the reaction rate. This type of reaction is referred to as a catalytic reaction. Catalytic reactions are different from stoichiometric reactions. The reaction rate of a stoichiometric reaction depends on the concentrations of reactants.Do your (or your lab section’s) results and observations confirm that one of the two gas-forming reactions is catalytic? (Hint: Think about the definition of a catalyst.) Support your answer and indicate which gas-forming reaction is catalytic. (6 pts)2. For the reaction of zinc with hydrochloric acid to produce H2, which reactant (zinc or H+) is used up first. Support your answer based on the number of moles calculated in the data analysis section above. (6 pts)3. Based on your (or your lab section’s) results and observations, is the combustion reaction of hydrogen with oxygen endothermic or exothermic? Support your answer. (6 pts)4. Name at least four possible factors that impact propulsion of the rocket in this experiment. Also indicate which factor (i.e., independent variable) you chose for propulsion optimization. (5 pts)Click or tap here to enter text.5. Considering the data from your entire lab section, which factor played the biggest role in affecting rocket propulsion? Support your answer. (6 pts)Click or tap here to enter text.6. Considering the measurements made during experiment 5, identify at least one possible source of error (besides human error). Note whether the error(s) would i) be random or systematic, ii) affect accuracy or precision, and iii) be expected to be significant enough to impact the determination of which factor affects rocket propulsion the most.For systematic errors, state the quantity that would be affected and, if possible, how it would be affected (e.g., … would be artificially higher than …). (6 pts)Click or tap here to enter text.TA ONLY (Grade Last): Formatting Late PenaltyName Jamoni CollinsLabPartner(s)Jordan Han ONYEN jjamoni(2 pt penaltyif missing)Jinjo, Briabri, Rand1209Template Instructions: Remove and replace any highlighted text. Do not resize, remove, or add answer boxes. Use data from your in-lab assignment to fill in the gray-shadedcells in the tables below.Experiment 5: Gas-Forming Reactionsand RocketsPost-Lab Results & Data AnalysisRESULTS: The “Results” section of a published article is where the data is presented (most often) through figures and tables. Answer boxes and fillable tables are provided below for you to present your data from experiment 1. Include a caption for each figure and a title for each table. Construct figures and fill in tables using your in-lab measurements and recorded data as appropriate. Also include a simple description of the figure data. See notes and examples below.Note on Figure Captions: A proper caption provides enough information about the graph that the reader understands what is being displayed. According to American Chemical Society (ACS) guidelines1, the reader should be able to understand the caption without reference to the text or, in this case, the lab manual. For graphs that include experimental data, include relevant measurement conditions such that the reader can understand not only what the data is but also how the data was collected could repeat the measurement, if so desired. The first sentence can be a sentence fragment but doesn’t have to be.1: https://pubs.acs.org/doi/full/10.1021/acsguide.40303Example of a Figure Caption: “Reaction yield as a function of added catalyst with reaction yield determined by absorption measurements. Reactions were held at a constant temperature of 22±2/°C. Concentrations of all other reactants were kept constant at the values shown in Table/9. Each data point is the average of three trials.”-NOTE TO STUDENTS: Don’t feel the need to include things just to make the caption longer. As a start, aim for something similar to the first sentence of the figure caption example (what is being displayed in the figure) and include one other sentence that plainly states a relevant measurement condition (e.g., the temperature of the solution was allowed to equilibrate for 5 min. before recordingeach measurement.) If other (obviously important) measurement conditions are identified, those can be included but the main goal here is learning what to include in the caption, not making a lengthy caption.Also, in the example figure caption above, the end of the first sentence states, “…with reaction yielddetermined by absorption measurements”. The general idea is to state what experimental technique was used to determine the dependent variable values, which was “reaction yield” in this example. This information is needed in a figure caption for experimental data.1CHEM 101L Post-Lab Assignment: Experiment 5 Spring 2022Note on Table Titles: The ACS states that each table must include a one phrase (or sentence) title that describes the contents of the table. The title should be understandable without reference to the textor, in this case, the lab manual.1Example of a Table Title: “Rate constants for substitution reaction A as a function of temperature.”Note on Units for Table Entries: For each entry in a table, units should be included, either in the column header or in a separate column (similar to how units are treated in Excel), unless the quantity isactually unitless. The ACS does not require a separate column for units in a table but is requested hereto avoid confusion.Note on Description of Data: In addition to tables and figures, the Results section includes text describing the results displayed in the figures and tables. Space is provided below for you to provide a description of data displayed in the figures. To simplify this post-lab assignment, a description of the tables will not be included at this time.Example of Description of Figure Data: “Figure 5 displays the reaction rate measured as a function of temperature for each of the catalysts used here. Each data set was modeled using an exponential function with the best


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