Im having trouble believing that the answers I arrived too are incorrect.
Posted: Mon Jul 11, 2022 1:54 pm
Im having trouble believing that the answers I arrived too are incorrect.
1. Calculate the concentration of OH in NAOH solutions #2 and # 3. A. Using your answers to question 1, calculate the concentration of OH in the reaction vessels for all three trials. ** B. Determine which plot is closest to linear by fitting each with a trendline and comparing R? values. Using this information, report the order of crystal violet (x) in the reaction. C. Using the equation of your trendline, report the pseudo rate constant (k'), including units. Be sure that your slope has two significant figures. To change the number of digits displayed, right click on the equation box on your graph and select "Format Trendline Label". D. Using [OH-] and k' values for trials 2 and 3, determine the order of OH- (y). Use the pseudo rate constant equation (k'= k [OH-]^ y). HINT: you can find the answer either by inspection or by using algebra **HINT: the value should be either O, 1, or 2. E. Using the value of y determined in (7), your k' values from (5), and the pseudo rate constant equation, calculate the overall rate constant (k) for each trial. Then, calculate the average of those three values. ** If you believe one of these k values should be excluded from the average, feel free to do so - but make sure to address your reasoning in the conclusions! F. Write the complete rate law by replacing k, x, and y with your experimentally determined values. ratek [Cv+]^x [OH-]^y
Procedure Students will work in pairs. Part I: Instrumentation Setup a. From the equipment drawer below your hood, remove the... i. Laptop ii. Laptop Power Cord iii. Colorimeter box (contains Colorimeter and 2 cuvettes) iv. LabQuest mini box (contains LabQuest Mini and USB Cable) b. Leave all other equipment in the drawer. c. You will be responsible for any damage to the equipment, so be careful! 2. Place the laptop on top of the blue plastic lid on one side of your fume hood. Plug in and turn on the computer. Log in using your own credentials. Connect the LabQuest Mini to the computer by placing one end of the cable into the computer's USB port and the other end into the port on the LabQuest Mini marked with the USB symbol (). 3. Insert the colorimeter's cable into the CH1 port on the side of the LabQuest Mini. 4. Launch the Logger Pro software on the laptop. The software will automatically identify that the colorimeter is connected and display the real-time % transmittance measurement in the bottom left portion of the screen. Part II: Prepare Solutions Be very careful to keep the crystal violet and NaOH solutions separate until you are ready to collect the experimental data (see Part IV below). It is important to be familiar with how to use volumetric pipets and flasks, as described in "Standard Operating Procedures for Special Techniques", provided via Brightspace. Please work with the chemicals on the side of your fume hood opposite the computer. 5. Obtain around 30 mL of the provided 5.0x10-5 M crystal violet solution. Place it in a very small beaker to make pipetting easier. 6. Obtain a 5-mL volumetric pipet. Rinse it with DI water once and with the crystal violet stock solution twice. Discard all rinse liquids into a labeled waste beaker.
7. The crystal violet stock solution will be used for all three experimental trials. To prepare for the experiment: a. Obtain three small test tubes and label them. b. Pipet 5.00 mL of the crystal violet solution into each test tube and set them aside. 8. Obtain around 75 mL of the provided "0.20 M NaOH solution and place it in a small beaker. Make sure to write down the exact concentration of the solution. 9. For experimental trial 1, you will use 5 mL of the stock ~0.20 NaOH solution. a. Rinse the 5-mL volumetric pipet with DI water once and with the NaOH stock solution twice. Ensure that all the crystal violet is out of the pipet. b. Pipet 5.00 mL of 0.20 M NaOH into a clean and labeled large test tube. Set it aside. 10. For experimental trial 2, you will use a diluted NaOH solution. a. Obtain a clean 100-ml volumetric flask. b. Obtain a 25-mL volumetric pipet. Rinse it with DI water once and with the NaOH stock solution twice. c. Pipet 50.00 mL of the "0.20 M NaOH solution into the 100-mL volumetric flask. d. Carefully fill the volumetric flask with DI water, making sure the solution is well mixed. We will call this "NaOH solution #2." e. Once mixed, pour NaOH solution #2 into a clean, labeled beaker. f. Rinse the 5-mL volumetric pipet with DI water once and with NaOH solution #2 twice. 8. Pipet 5.00 mL of NaOH solution #2 into a clean and labeled large test tube. 11. For Experimental trial 3, will use an even more dilute NaOH solution. a. Rinse out the 100-mL volumetric flask several times with DI water. b. Rinse the 25-mL volumetric pipet with DI water once and with NaOH solution #2 twice. c. Pipet 50.00 mL of NaOH solution #2 into the 100-ml volumetric flask. d. Carefully fill the volumetric flask with DI water, making sure the solution is well mixed. We will call this "NaOH solution #3." e. Once mixed, pour NaOH solution #3 into a clean, labeled beaker. f. Rinse the 5-mL volumetric pipet with DI water once and with NaOH solution #3 twice. g. Pipet 5.00 mL of NaOH solution #3 into a clean and labeled large test tube. Keep all dilutions until the end of the experiment in case you would like to repeat a trial.
Part III: Calibrate Colorimeter and Prepare for Data Collection 12. Inspect your cuvettes. a. They will have two smooth sides and two ribbed sides. b. The light is transmitted through the smooth sides, so ensure that these sides are clean and free of any damage. c. Only handle the cuvettes by the top edge of the ribbed sides. Avoid activities that may scratch the sides of the cuvette. d. Before placing the cuvette in the colorimeter, always wipe the smooth side with lint- free tissue (Kim-wipes, in the little green box). e. Do not wipe the inside of the cuvette. Instead, rinse it with the appropriate solution. 13. The colorimeter must be calibrated before using it. Don't begin this step until the colorimeter has been powered on for at least 5 minutes. a. Select the correct wavelength on the colorimeter. Press the <or > button on the front of the colorimeter to select the 565 nm wavelength. b. Clean a plastic cuvette with Dl water. c. Fill the cuvette at least % full with DI water. If there are air bubbles present in the cuvette, gently tap the cuvette on a hard surface to dislodge the bubbles. d. On the computer: i. Open the Experiment menu at the top. ii. Select Calibrate and then select the LabQuest Mini: Colorimeter. iii. A window called Sensor Settings should appear. Click on the Calibrate tab. iv. Click on the Calibrate Now button to begin the calibration process. e. Wipe the smooth sides of the cuvette using a Kim-wipe. f. Insert the cuvette with the DI water into the colorimeter. The smooth sides of the cuvette should align with the white triangle inside the colorimeter. Close the lid. g. In the box labeled Reading 1:, type 100.00 into the box (%T). Click Keep. Now the second box, Reading 2:, will be selected. h. Obtain ~10 mL of the Calibration Solution from the reagent hood. Record the exact value of the transmittance written on the solution in your lab notebook. You will need this value later for calibration. i. Alternatively, there may be several cuvettes already filled with the calibration solution in the reagent hood. If this is the case, skip step i and use one of these cuvettes for steps j-l below. i. Rinse the cuvette twice with the Calibration Solution and then fill the cuvette to at least % full. j. Wipe the cuvette with a Kim-wipe, then put it into the colorimeter. Close the lid.
k. Enter the percent transmittance of the Calibration Solution in the Reading 2 box and click Keep. 1. Click Done to close the window and apply the calibration. m. Remove the cuvette. Now the colorimeter is ready to use! 14. Place the cuvette with the Calibration Solution back into the colorimeter (after wiping down the sides with a Kim-wipe) and verify the transmittance reading. It should match the value you have written down. 15. Rinse the cuvette well, fill it % full with DI water, and place it in the colorimeter. Verify that the % transmittance is 100. 16. Open the data collection window by clicking on the icon in the toolbar (or by selecting Data Collection from the experiment menu). Use this window to modify the settings of the data acquisition. Change the settings to match those shown in the screenshot at right. a. Set the "length" of the experiment to 5 minutes (300 seconds) b. Record an absorbance measurement every four seconds ("seconds/sample") c. Press Done when you are finished. Data Collection Collection Triggering Mode: Time Based seconds Contnuous Data Collection Length: 300 Perform steps 19-28 for each of the three trials. Sampling Rate: samples/second Oversamping Help 4 Bepent Sample at Time Zero Triggering disabled seconds/sample Samples to be collected: Trial #1: 5.00 mL 5.0x105 M crystal violet + 5.00 mL 0.20 M NaOH Trial #2: 5.00 mL 5.0x10-5 M crystal violet + 5.00 mL NaOH solution #2 Trial #3: 5.00 mL 5.0x10-5 M crystal violet + 5.00 mL NaOH solution #3 Done The software is now ready to collect data. 17. Create a floating window to display the real-time absorbance value by selecting Insert → Meter → Digital Meter. Drag this window to a suitable location within the main Logger Pro window. Cancel Part IV: Run the Reactions and Collect Data 18. You are now ready to collect your experimental data. Arrange your test tubes so the correct solutions will be mixed:
Read and contemplate these steps in advance so that you can perform them quickly. 19. Initiate the reaction by pouring the 5 mL aliquot of crystal violet into the the sample of NaOH, covering the test tube with parafilm, and inverting it 3 times to mix. 20. Start the acquisition as soon as the mixing begins by pressing Collect. Note: start the acquisition even though your cuvette is not yet in the spectrometer to capture the start of the reaction and to get a baseline. 21. After the solution is mixed, quickly rinse the cuvette twice with a small amount of the reaction mixture. Then fill the cuvette 3/4 full of the solution and wipe down the smooth sides with a kimwipe. 22. Quickly place the cuvette in the colorimeter, remembering to align the smooth sides of the cuvette with the path of the light. Close the lid. If liquid lands on the outside of the cuvette during pouring, wipe it off with a lint-free tissue. 23. The absorbance data will be collected the length of time you selected above. The Logger Pro program will plot the data in real time. If you wish, you may autoscale the graph by pressing the button in the toolbar, to the left of the collect button. While your reaction is running, you can visually monitor the progress of the reaction by looking at the CV'/NaOH mixture remaining in your test tube. As the reaction proceeds the solution will gradually lose its color. This process is quantitatively measured by the colorimeter. 24. After the prescribed time your data collection will be complete. This is indicated by the collect button turning green again. Do not remove your cuvette from the colorimeter yet. 25. Export the data (File → Export As → CSV) and save the file to the desktop with an appropriate name. You will eventually save three reaction runs, so name your files accordingly. 26. Now that your data has been saved as a CSV (comma-separated values) file, you can clear your data from the active window by selecting Data → Clear All Data. 27. When you process your data you will need the absorbance of your reaction solution after the reaction has fully reached completion (A at infinite time, or A.). The reaction didn't reach completion during the data collection. To measure A-, monitor the real-time absorbance value displayed on the laptop. When this value doesn't change for over 20 s, write it down as A-. a. If it has been 8 minutes since your acquisition finished and the absorbance value is still slowly changing, write down the current value as A- and proceed with the experiment. 28. After you have measured A., remove the cuvette from the colorimeter and empty your finished reaction solution into a waste beaker. Rinse your cuvette with deionized water several times and dry the outside with a lint-free tissue. Be sure to wipe off the colorimeter to ensure that any spilled solution does not dry inside.
40 0.127906 74.40935 44 0.126033 74.81122 48 0.125531 74.39781 52 0.123353 75.27426 56 0.122941 75.34579 60 0.121847 75.5359 64 0.1215 75.59613 68 0.119968 75.86342 72 0.119698 75.91048 76 0.118762 76.07424 80 0.117957 76.21541 84 0.116918 76.39799 88 0.11457 76.81209 92 0.112309 77.21302 96 0.114922 76.74998 100 0.114507 76.82339 104 0.113582 76.98715 108 0.111749 77.31278 112 0.112415 77.1942 116 0.112521 77.17537 120 0.111728 77.31655 124 0.111146 77.42007 128 0.107362 78.0977 132 0.11064 7751042 136 0.109785 77.66289 140 0.110208 77.5876 144 0.108169 77.95276 148 0.107393 78.09205 152 0.108767 77.84547 156 0.108315 77.92641 160 0.108074 77.9697 164 0.107802 78.01864 168 0.107079 78.14852 172 0.107414 78.08828 176 0.104545 78.60591 180 0.106557 78.24263 184 0.106285 78.29157 188 0.105774 78.3838 192 0.105565 78.42145 196 0.102546 78.95037 200 0.10543 7844592 204 0.104899 78.54192 208 0.102345 79.00496 212 0.104077 78.69062 216 0.104722 78.57391 220 0.099078 79.60164 224 0.102294 79.01437 228 0.103268 78.83743 232 0.101963 79.0746 236 0.101715 79.11978 240 0.096518 80.07222 244 0.099417 79.53953 248 0.102439 78.98802 252 0.100807 79.28542 256 0.101932 79.08025 260 0.100899 79.26848 SPERIME 034 0.32 8.1 ! 4 0.04 6.00 96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 248 256 264 272 280 288 296 Latest: Times P
9012BH56789012BH56782和H2B5拓初粥的和F轻铝锅钻钻中能鸦和弘放到另5%望8卵和机应3科55 14 33 34 40 41 42 43 44 45 46 47 48 49 54 64 Latest: Time() 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 GE 72 76 80 84 88 92 96 100 104 100 112 116 120 124 128 132 136 140 144 148 152 156 160 164 168 172 176 180 184 188 192 196 200 204 200 212 216 220 224 228 232 236 240 244 248 252 B 146 CD E Latest: Ab Latest: Transmittance (NT) 0,023368 84.44289 0,024153 84.41465 0.022205 84.41277 0.021379 84.40336 0.024473 84.59724 0.022403 84.3676 0.022799 87.23056 0.022902 77.5236 0.020624 74.35947 0.021259 74.35382 0.275607 74.48935 0.343733 74.81122 0.340122 74.89781 0.330638 75.27426 0.325038 75.34579 0.31951 75.5359 0.314084 75.59613 0.307413 75.86342 0.301891 75.91048 0.291163 76.07424 0.288836 76.21541 0.278562 76.39799 0.279759 76.81209 0.275376 77.21302 0.269437 76.74998 0.265366 7682339 0.261692 76.98715 0.25725 77.31278 0.252852 77.1942 0.246058 77.17537 0.243902 77.31655 0.238744 77 42007 0.236653 78.0977 0.233688 77.51042 0.229814 77.66289 0.224202 77.5876 0.216167 77.95276 0.213981 78.09205 0.213072 77.84547 0.209204 77.92641 0.210423 77.9697 0.204243 78.01864 0.202807 78.14852 0.201219 78.08828 0.199016 78.60591 0.196387 78.24263 0.192702 78.29157 0.188619 783838 0.18131 78.42145 0.187359 78.95037 0.184124 78.44592 0.182316 78.54192 0.180442 79.00496 0.177824 78.69062 0.177123 78.57391 0.173817 79.60164 0.170766 79.01437 0.171324 78.83743 0.162072 79.0746 0.167652 79.11978 0.162833 80.07222 0.164632 79.53953 0.155007 78.96802 0.157654 79.28542 16036 04 0.35 La Absorbance 0.3 0.25 0.2 0.35 0.1 0.05 G 1624324 0 Trail 2: Absorbance Vs. Time (s) o 112120128 136 144 152 180 168 176 184 182 200 208 216 214 212 240 248 256 264 272 280 288296 Latest
NHULDENRINDH5SD西西和12站HK拓习期签船载程们科特布非领的见狂位妇只猪猪 24 26 27 32 33 34 35 36 37 38 39 42 43 53 54 54 55 56 57 50 59 60 61 833333333 62 63 64 65 66 67 PA Latest Time 12 16 20 24 *******⠀⠀⠀⠀⠀⠀⠀******************************** B с D E F Latest: Ab Latest: Transmitance (NT) 8996-05 9997929 4.9105 99.98871 3.276-05 99.99247 0.000196 39.95483 0.00018 99.95859 0.000131 99.96988 0.000114 99.97365 0.021732 1 95.11923 6.02095 95.38299 0026971 93.97856 0.0001729996047 קרררר 3.276-05 99.99247 0.022471 94.95735 Pow 0.294565 50.74993 M 0.355008 44.15628 www 0.355174 44.13914 0.352239 44.43862 0.342364 45.4607 0.340104 45.65767 ************** 0.337411 45.3821 0331461 46.63643 0.325591 47.25076 032021 4783991 0.317824 48.10343 0.317858 48.09967 0.313108 48.62859 0.309526 49.0314 0.301956 49.89349 0.303367 49.73161 www 0.297977 50.35277 TRAPER **** 0.291579 51.10004 0.291483 51.1113 wow summ 0291579 51.10004 HORTS STA 0.283464 52.06377 Lesser Pro 0281647 52.28211 0.279012 52.60022 0274083 53.20067 027643 33.00 0.275746 52.99738 0.365095 $4.3131 0.269406 53.77665 0.265306 54.28675 0.262619 54.62368 0.361235 5480062 4352 0258273 55.17331 ****** 0257176 55.3126 A 0.254553 02480 **** 0247775 56.52291 0241244 0.243344 0.24727 56.58679 5738365 57.30365 57.38547 0.242734 0.241672 57.32288 0.337867 57.83733 0.237485 57.87836 38.11909 0.235641 6.350786 56.77769 0229566 588 0.229966 58.88 0725483 18.09615 AT T 0.222139 59.9999 0.225725 39.46681 0.221046 59.99761 0.220546 60.18019 6031364 60.86138 55.64764 s SEGONS www 0.219583 0.215657 0215831608371 0214155630724 in + Calidation Movie Automate Workhon G H Lance 1 40000 3301 100001 250 13041 150 no 2005 L M N O P S Trail 3: Absorbance vs Time (s) IN44151014 V W X Y MEWHERE THE
Transmittance - 58.77% ← Citbration Solution The solution lust its color after 3 minutes. t cat3 50m Waolt + rome DI -Strom #2 +50m] Cyrastal Vielet + 5.00mm 0.20μ1 MOH 5.0×10 "Tal Cyrystel violet + 5.00ml NaOH Sol. #2 Trail #3:5pL 5.0x10-5M Crystal Vialet + 5.00mc No Olt Sol. #3 Sol.2 Absorbance 0.149 Trail #1: 5m² ** Trail #C: 5m² - fransmittance - 71% 5.0×10-m SML Sms E sur < Sd. B Absorbance - €0.7287 0.12% transmittance - 7663.9 15.48% T Sol 1. 5mc #Crystal Violet 45mc 0.2011 NaOH Sol 2. 5mL Crystal Violet & Sme NaOH Sol #2 (50mL Noot + Ome Sol 3. 5ome Crystal Violet + 5m Nalltsd #3 (50mc NAGH.H2 + come
1. Calculate the concentration of OH in NAOH solutions #2 and #3. A. Using your answers to question 1, calculate the concentration of OH in the reaction vessels for all three trials. B. Determine which plot is closest to linear by fitting each with a trendline and comparing R? values. Using this information, report the order of crystal violet (x) in the reaction. C. Using the equation of your trendline, report the pseudo rate constant (k'), including units. Be sure that your slope has two significant figures. To change the number of digits displayed, right click on the equation box on your graph and select "Format Trendline Label". D. Using [OH-] and k' values for trials 2 and 3, determine the order of OH- (y). Use the pseudo rate constant equation (k'= k [OH-]^ y). ** HINT: you can find the answer either by inspection or by using algebra **HINT: the value should be either O. 1, or 2. E. Using the value of y determined in (7), your k' values from (5), and the pseudo rate constant equation, calculate the overall rate constant (k) for each trial. Then, calculate the average of those three values. ** If you believe one of these k values should be excluded from the average, feel free to do so - but make sure to address your reasoning in the conclusions! F. Write the complete rate law by replacing k, x, and y with your experimentally determined values. ratek [Cv+]^x [OH-]^y
1. Calculate the concentration of OH in NAOH solutions #2 and # 3. A. Using your answers to question 1, calculate the concentration of OH in the reaction vessels for all three trials. ** B. Determine which plot is closest to linear by fitting each with a trendline and comparing R? values. Using this information, report the order of crystal violet (x) in the reaction. C. Using the equation of your trendline, report the pseudo rate constant (k'), including units. Be sure that your slope has two significant figures. To change the number of digits displayed, right click on the equation box on your graph and select "Format Trendline Label". D. Using [OH-] and k' values for trials 2 and 3, determine the order of OH- (y). Use the pseudo rate constant equation (k'= k [OH-]^ y). HINT: you can find the answer either by inspection or by using algebra **HINT: the value should be either O, 1, or 2. E. Using the value of y determined in (7), your k' values from (5), and the pseudo rate constant equation, calculate the overall rate constant (k) for each trial. Then, calculate the average of those three values. ** If you believe one of these k values should be excluded from the average, feel free to do so - but make sure to address your reasoning in the conclusions! F. Write the complete rate law by replacing k, x, and y with your experimentally determined values. ratek [Cv+]^x [OH-]^y
Procedure Students will work in pairs. Part I: Instrumentation Setup a. From the equipment drawer below your hood, remove the... i. Laptop ii. Laptop Power Cord iii. Colorimeter box (contains Colorimeter and 2 cuvettes) iv. LabQuest mini box (contains LabQuest Mini and USB Cable) b. Leave all other equipment in the drawer. c. You will be responsible for any damage to the equipment, so be careful! 2. Place the laptop on top of the blue plastic lid on one side of your fume hood. Plug in and turn on the computer. Log in using your own credentials. Connect the LabQuest Mini to the computer by placing one end of the cable into the computer's USB port and the other end into the port on the LabQuest Mini marked with the USB symbol (). 3. Insert the colorimeter's cable into the CH1 port on the side of the LabQuest Mini. 4. Launch the Logger Pro software on the laptop. The software will automatically identify that the colorimeter is connected and display the real-time % transmittance measurement in the bottom left portion of the screen. Part II: Prepare Solutions Be very careful to keep the crystal violet and NaOH solutions separate until you are ready to collect the experimental data (see Part IV below). It is important to be familiar with how to use volumetric pipets and flasks, as described in "Standard Operating Procedures for Special Techniques", provided via Brightspace. Please work with the chemicals on the side of your fume hood opposite the computer. 5. Obtain around 30 mL of the provided 5.0x10-5 M crystal violet solution. Place it in a very small beaker to make pipetting easier. 6. Obtain a 5-mL volumetric pipet. Rinse it with DI water once and with the crystal violet stock solution twice. Discard all rinse liquids into a labeled waste beaker.
7. The crystal violet stock solution will be used for all three experimental trials. To prepare for the experiment: a. Obtain three small test tubes and label them. b. Pipet 5.00 mL of the crystal violet solution into each test tube and set them aside. 8. Obtain around 75 mL of the provided "0.20 M NaOH solution and place it in a small beaker. Make sure to write down the exact concentration of the solution. 9. For experimental trial 1, you will use 5 mL of the stock ~0.20 NaOH solution. a. Rinse the 5-mL volumetric pipet with DI water once and with the NaOH stock solution twice. Ensure that all the crystal violet is out of the pipet. b. Pipet 5.00 mL of 0.20 M NaOH into a clean and labeled large test tube. Set it aside. 10. For experimental trial 2, you will use a diluted NaOH solution. a. Obtain a clean 100-ml volumetric flask. b. Obtain a 25-mL volumetric pipet. Rinse it with DI water once and with the NaOH stock solution twice. c. Pipet 50.00 mL of the "0.20 M NaOH solution into the 100-mL volumetric flask. d. Carefully fill the volumetric flask with DI water, making sure the solution is well mixed. We will call this "NaOH solution #2." e. Once mixed, pour NaOH solution #2 into a clean, labeled beaker. f. Rinse the 5-mL volumetric pipet with DI water once and with NaOH solution #2 twice. 8. Pipet 5.00 mL of NaOH solution #2 into a clean and labeled large test tube. 11. For Experimental trial 3, will use an even more dilute NaOH solution. a. Rinse out the 100-mL volumetric flask several times with DI water. b. Rinse the 25-mL volumetric pipet with DI water once and with NaOH solution #2 twice. c. Pipet 50.00 mL of NaOH solution #2 into the 100-ml volumetric flask. d. Carefully fill the volumetric flask with DI water, making sure the solution is well mixed. We will call this "NaOH solution #3." e. Once mixed, pour NaOH solution #3 into a clean, labeled beaker. f. Rinse the 5-mL volumetric pipet with DI water once and with NaOH solution #3 twice. g. Pipet 5.00 mL of NaOH solution #3 into a clean and labeled large test tube. Keep all dilutions until the end of the experiment in case you would like to repeat a trial.
Part III: Calibrate Colorimeter and Prepare for Data Collection 12. Inspect your cuvettes. a. They will have two smooth sides and two ribbed sides. b. The light is transmitted through the smooth sides, so ensure that these sides are clean and free of any damage. c. Only handle the cuvettes by the top edge of the ribbed sides. Avoid activities that may scratch the sides of the cuvette. d. Before placing the cuvette in the colorimeter, always wipe the smooth side with lint- free tissue (Kim-wipes, in the little green box). e. Do not wipe the inside of the cuvette. Instead, rinse it with the appropriate solution. 13. The colorimeter must be calibrated before using it. Don't begin this step until the colorimeter has been powered on for at least 5 minutes. a. Select the correct wavelength on the colorimeter. Press the <or > button on the front of the colorimeter to select the 565 nm wavelength. b. Clean a plastic cuvette with Dl water. c. Fill the cuvette at least % full with DI water. If there are air bubbles present in the cuvette, gently tap the cuvette on a hard surface to dislodge the bubbles. d. On the computer: i. Open the Experiment menu at the top. ii. Select Calibrate and then select the LabQuest Mini: Colorimeter. iii. A window called Sensor Settings should appear. Click on the Calibrate tab. iv. Click on the Calibrate Now button to begin the calibration process. e. Wipe the smooth sides of the cuvette using a Kim-wipe. f. Insert the cuvette with the DI water into the colorimeter. The smooth sides of the cuvette should align with the white triangle inside the colorimeter. Close the lid. g. In the box labeled Reading 1:, type 100.00 into the box (%T). Click Keep. Now the second box, Reading 2:, will be selected. h. Obtain ~10 mL of the Calibration Solution from the reagent hood. Record the exact value of the transmittance written on the solution in your lab notebook. You will need this value later for calibration. i. Alternatively, there may be several cuvettes already filled with the calibration solution in the reagent hood. If this is the case, skip step i and use one of these cuvettes for steps j-l below. i. Rinse the cuvette twice with the Calibration Solution and then fill the cuvette to at least % full. j. Wipe the cuvette with a Kim-wipe, then put it into the colorimeter. Close the lid.
k. Enter the percent transmittance of the Calibration Solution in the Reading 2 box and click Keep. 1. Click Done to close the window and apply the calibration. m. Remove the cuvette. Now the colorimeter is ready to use! 14. Place the cuvette with the Calibration Solution back into the colorimeter (after wiping down the sides with a Kim-wipe) and verify the transmittance reading. It should match the value you have written down. 15. Rinse the cuvette well, fill it % full with DI water, and place it in the colorimeter. Verify that the % transmittance is 100. 16. Open the data collection window by clicking on the icon in the toolbar (or by selecting Data Collection from the experiment menu). Use this window to modify the settings of the data acquisition. Change the settings to match those shown in the screenshot at right. a. Set the "length" of the experiment to 5 minutes (300 seconds) b. Record an absorbance measurement every four seconds ("seconds/sample") c. Press Done when you are finished. Data Collection Collection Triggering Mode: Time Based seconds Contnuous Data Collection Length: 300 Perform steps 19-28 for each of the three trials. Sampling Rate: samples/second Oversamping Help 4 Bepent Sample at Time Zero Triggering disabled seconds/sample Samples to be collected: Trial #1: 5.00 mL 5.0x105 M crystal violet + 5.00 mL 0.20 M NaOH Trial #2: 5.00 mL 5.0x10-5 M crystal violet + 5.00 mL NaOH solution #2 Trial #3: 5.00 mL 5.0x10-5 M crystal violet + 5.00 mL NaOH solution #3 Done The software is now ready to collect data. 17. Create a floating window to display the real-time absorbance value by selecting Insert → Meter → Digital Meter. Drag this window to a suitable location within the main Logger Pro window. Cancel Part IV: Run the Reactions and Collect Data 18. You are now ready to collect your experimental data. Arrange your test tubes so the correct solutions will be mixed:
Read and contemplate these steps in advance so that you can perform them quickly. 19. Initiate the reaction by pouring the 5 mL aliquot of crystal violet into the the sample of NaOH, covering the test tube with parafilm, and inverting it 3 times to mix. 20. Start the acquisition as soon as the mixing begins by pressing Collect. Note: start the acquisition even though your cuvette is not yet in the spectrometer to capture the start of the reaction and to get a baseline. 21. After the solution is mixed, quickly rinse the cuvette twice with a small amount of the reaction mixture. Then fill the cuvette 3/4 full of the solution and wipe down the smooth sides with a kimwipe. 22. Quickly place the cuvette in the colorimeter, remembering to align the smooth sides of the cuvette with the path of the light. Close the lid. If liquid lands on the outside of the cuvette during pouring, wipe it off with a lint-free tissue. 23. The absorbance data will be collected the length of time you selected above. The Logger Pro program will plot the data in real time. If you wish, you may autoscale the graph by pressing the button in the toolbar, to the left of the collect button. While your reaction is running, you can visually monitor the progress of the reaction by looking at the CV'/NaOH mixture remaining in your test tube. As the reaction proceeds the solution will gradually lose its color. This process is quantitatively measured by the colorimeter. 24. After the prescribed time your data collection will be complete. This is indicated by the collect button turning green again. Do not remove your cuvette from the colorimeter yet. 25. Export the data (File → Export As → CSV) and save the file to the desktop with an appropriate name. You will eventually save three reaction runs, so name your files accordingly. 26. Now that your data has been saved as a CSV (comma-separated values) file, you can clear your data from the active window by selecting Data → Clear All Data. 27. When you process your data you will need the absorbance of your reaction solution after the reaction has fully reached completion (A at infinite time, or A.). The reaction didn't reach completion during the data collection. To measure A-, monitor the real-time absorbance value displayed on the laptop. When this value doesn't change for over 20 s, write it down as A-. a. If it has been 8 minutes since your acquisition finished and the absorbance value is still slowly changing, write down the current value as A- and proceed with the experiment. 28. After you have measured A., remove the cuvette from the colorimeter and empty your finished reaction solution into a waste beaker. Rinse your cuvette with deionized water several times and dry the outside with a lint-free tissue. Be sure to wipe off the colorimeter to ensure that any spilled solution does not dry inside.
40 0.127906 74.40935 44 0.126033 74.81122 48 0.125531 74.39781 52 0.123353 75.27426 56 0.122941 75.34579 60 0.121847 75.5359 64 0.1215 75.59613 68 0.119968 75.86342 72 0.119698 75.91048 76 0.118762 76.07424 80 0.117957 76.21541 84 0.116918 76.39799 88 0.11457 76.81209 92 0.112309 77.21302 96 0.114922 76.74998 100 0.114507 76.82339 104 0.113582 76.98715 108 0.111749 77.31278 112 0.112415 77.1942 116 0.112521 77.17537 120 0.111728 77.31655 124 0.111146 77.42007 128 0.107362 78.0977 132 0.11064 7751042 136 0.109785 77.66289 140 0.110208 77.5876 144 0.108169 77.95276 148 0.107393 78.09205 152 0.108767 77.84547 156 0.108315 77.92641 160 0.108074 77.9697 164 0.107802 78.01864 168 0.107079 78.14852 172 0.107414 78.08828 176 0.104545 78.60591 180 0.106557 78.24263 184 0.106285 78.29157 188 0.105774 78.3838 192 0.105565 78.42145 196 0.102546 78.95037 200 0.10543 7844592 204 0.104899 78.54192 208 0.102345 79.00496 212 0.104077 78.69062 216 0.104722 78.57391 220 0.099078 79.60164 224 0.102294 79.01437 228 0.103268 78.83743 232 0.101963 79.0746 236 0.101715 79.11978 240 0.096518 80.07222 244 0.099417 79.53953 248 0.102439 78.98802 252 0.100807 79.28542 256 0.101932 79.08025 260 0.100899 79.26848 SPERIME 034 0.32 8.1 ! 4 0.04 6.00 96 104 112 120 128 136 144 152 160 168 176 184 192 200 208 216 224 232 240 248 256 264 272 280 288 296 Latest: Times P
9012BH56789012BH56782和H2B5拓初粥的和F轻铝锅钻钻中能鸦和弘放到另5%望8卵和机应3科55 14 33 34 40 41 42 43 44 45 46 47 48 49 54 64 Latest: Time() 8 12 16 20 24 28 32 36 40 44 48 52 56 60 64 GE 72 76 80 84 88 92 96 100 104 100 112 116 120 124 128 132 136 140 144 148 152 156 160 164 168 172 176 180 184 188 192 196 200 204 200 212 216 220 224 228 232 236 240 244 248 252 B 146 CD E Latest: Ab Latest: Transmittance (NT) 0,023368 84.44289 0,024153 84.41465 0.022205 84.41277 0.021379 84.40336 0.024473 84.59724 0.022403 84.3676 0.022799 87.23056 0.022902 77.5236 0.020624 74.35947 0.021259 74.35382 0.275607 74.48935 0.343733 74.81122 0.340122 74.89781 0.330638 75.27426 0.325038 75.34579 0.31951 75.5359 0.314084 75.59613 0.307413 75.86342 0.301891 75.91048 0.291163 76.07424 0.288836 76.21541 0.278562 76.39799 0.279759 76.81209 0.275376 77.21302 0.269437 76.74998 0.265366 7682339 0.261692 76.98715 0.25725 77.31278 0.252852 77.1942 0.246058 77.17537 0.243902 77.31655 0.238744 77 42007 0.236653 78.0977 0.233688 77.51042 0.229814 77.66289 0.224202 77.5876 0.216167 77.95276 0.213981 78.09205 0.213072 77.84547 0.209204 77.92641 0.210423 77.9697 0.204243 78.01864 0.202807 78.14852 0.201219 78.08828 0.199016 78.60591 0.196387 78.24263 0.192702 78.29157 0.188619 783838 0.18131 78.42145 0.187359 78.95037 0.184124 78.44592 0.182316 78.54192 0.180442 79.00496 0.177824 78.69062 0.177123 78.57391 0.173817 79.60164 0.170766 79.01437 0.171324 78.83743 0.162072 79.0746 0.167652 79.11978 0.162833 80.07222 0.164632 79.53953 0.155007 78.96802 0.157654 79.28542 16036 04 0.35 La Absorbance 0.3 0.25 0.2 0.35 0.1 0.05 G 1624324 0 Trail 2: Absorbance Vs. Time (s) o 112120128 136 144 152 180 168 176 184 182 200 208 216 214 212 240 248 256 264 272 280 288296 Latest
NHULDENRINDH5SD西西和12站HK拓习期签船载程们科特布非领的见狂位妇只猪猪 24 26 27 32 33 34 35 36 37 38 39 42 43 53 54 54 55 56 57 50 59 60 61 833333333 62 63 64 65 66 67 PA Latest Time 12 16 20 24 *******⠀⠀⠀⠀⠀⠀⠀******************************** B с D E F Latest: Ab Latest: Transmitance (NT) 8996-05 9997929 4.9105 99.98871 3.276-05 99.99247 0.000196 39.95483 0.00018 99.95859 0.000131 99.96988 0.000114 99.97365 0.021732 1 95.11923 6.02095 95.38299 0026971 93.97856 0.0001729996047 קרררר 3.276-05 99.99247 0.022471 94.95735 Pow 0.294565 50.74993 M 0.355008 44.15628 www 0.355174 44.13914 0.352239 44.43862 0.342364 45.4607 0.340104 45.65767 ************** 0.337411 45.3821 0331461 46.63643 0.325591 47.25076 032021 4783991 0.317824 48.10343 0.317858 48.09967 0.313108 48.62859 0.309526 49.0314 0.301956 49.89349 0.303367 49.73161 www 0.297977 50.35277 TRAPER **** 0.291579 51.10004 0.291483 51.1113 wow summ 0291579 51.10004 HORTS STA 0.283464 52.06377 Lesser Pro 0281647 52.28211 0.279012 52.60022 0274083 53.20067 027643 33.00 0.275746 52.99738 0.365095 $4.3131 0.269406 53.77665 0.265306 54.28675 0.262619 54.62368 0.361235 5480062 4352 0258273 55.17331 ****** 0257176 55.3126 A 0.254553 02480 **** 0247775 56.52291 0241244 0.243344 0.24727 56.58679 5738365 57.30365 57.38547 0.242734 0.241672 57.32288 0.337867 57.83733 0.237485 57.87836 38.11909 0.235641 6.350786 56.77769 0229566 588 0.229966 58.88 0725483 18.09615 AT T 0.222139 59.9999 0.225725 39.46681 0.221046 59.99761 0.220546 60.18019 6031364 60.86138 55.64764 s SEGONS www 0.219583 0.215657 0215831608371 0214155630724 in + Calidation Movie Automate Workhon G H Lance 1 40000 3301 100001 250 13041 150 no 2005 L M N O P S Trail 3: Absorbance vs Time (s) IN44151014 V W X Y MEWHERE THE
Transmittance - 58.77% ← Citbration Solution The solution lust its color after 3 minutes. t cat3 50m Waolt + rome DI -Strom #2 +50m] Cyrastal Vielet + 5.00mm 0.20μ1 MOH 5.0×10 "Tal Cyrystel violet + 5.00ml NaOH Sol. #2 Trail #3:5pL 5.0x10-5M Crystal Vialet + 5.00mc No Olt Sol. #3 Sol.2 Absorbance 0.149 Trail #1: 5m² ** Trail #C: 5m² - fransmittance - 71% 5.0×10-m SML Sms E sur < Sd. B Absorbance - €0.7287 0.12% transmittance - 7663.9 15.48% T Sol 1. 5mc #Crystal Violet 45mc 0.2011 NaOH Sol 2. 5mL Crystal Violet & Sme NaOH Sol #2 (50mL Noot + Ome Sol 3. 5ome Crystal Violet + 5m Nalltsd #3 (50mc NAGH.H2 + come
1. Calculate the concentration of OH in NAOH solutions #2 and #3. A. Using your answers to question 1, calculate the concentration of OH in the reaction vessels for all three trials. B. Determine which plot is closest to linear by fitting each with a trendline and comparing R? values. Using this information, report the order of crystal violet (x) in the reaction. C. Using the equation of your trendline, report the pseudo rate constant (k'), including units. Be sure that your slope has two significant figures. To change the number of digits displayed, right click on the equation box on your graph and select "Format Trendline Label". D. Using [OH-] and k' values for trials 2 and 3, determine the order of OH- (y). Use the pseudo rate constant equation (k'= k [OH-]^ y). ** HINT: you can find the answer either by inspection or by using algebra **HINT: the value should be either O. 1, or 2. E. Using the value of y determined in (7), your k' values from (5), and the pseudo rate constant equation, calculate the overall rate constant (k) for each trial. Then, calculate the average of those three values. ** If you believe one of these k values should be excluded from the average, feel free to do so - but make sure to address your reasoning in the conclusions! F. Write the complete rate law by replacing k, x, and y with your experimentally determined values. ratek [Cv+]^x [OH-]^y