How Much Oxygen Gas is Produced WORKSHEET_Summer 2022

docx

School

Arizona State University *

*We aren’t endorsed by this school

Course

114

Subject

Chemistry

Date

Feb 20, 2024

Type

docx

Pages

Uploaded by jennxooxx

Lab Report Worksheet: How Much Oxygen Gas is Produced? Lab Section (or Day-Time): ____________________ Group Number: _________ Due Date: _______________ Name(s): __________________________________________________________________________________ This worksheet does not replace good lab notebook keeping! ALL INFORMATION RECORDED ON THIS WORKSHEET SHOULD COME FROM THE BOOK, PRELAB NOTES, THE LAB MANUAL AND EXPERIMENTAL VALUES/CALCULATIONS YOU HAVE RECORDED IN YOUR NOTEBOOK! 1. What is the goal of this investigation? 2. What is the reaction that will be taking place in the 125mL Erlenmeyer flask for this investigation? 3. What is the ideal gas law? Describe each variable and include units. 4. a. Draw the system that will be used for gas collection in the investigation, with some or all of the following equipment: ring stand with ring, 100 mL graduated cylinder, 125 mL Erlenmeyer flask, stopper with rigid tubing, flexible tubing, clear shoe storage bin, 600 mL beaker, tape (optional), and rubber band (optional). PROVIDE LABELS. Arizona State University School of Molecular Sciences 1

b. Discuss how you will find how much oxygen gas will be produced in the reaction using this set-up. (This should be a brief procedure). 5. Answer the following statements as True or False. a. _______. 30% Hydrogen peroxide is one of the chemicals used in today’s lab. b. _______. At least 2 trials are required for this investigation. c. _______. 5.00mL of a yeast solution will be used as a catalyst in the reaction. d. _______. The temperature of water from the 600mL must be recorded. e. _______. The atmospheric pressure of water is dependent on volume. 6. Table 1: Experimental Values and Data. Complete the following table with your experimental data for each of the two trials. Trial #1 Trial #2 (a) T: Temperature of H 2 O (K) Use Thermometer from drawer to take the temperature of the water (b) P H2O : Pressure of water vapor for this temp (mmHg) Look for it here: h t t p s : / / w w w 2 . d a w s o n c o l l e g e . q c . c a / d b a r i l / T o o l s / H 2 O _ V a p o r _ P r e s s u r e / H 2 O _ V a p P r e s s u r e H g . h t m Not necessary (c) P atmospheric : Atmospheric pressure (mmHg) TA will provide this number from Labquest and gas pressure sensor (d) Mass of dry yeast (g) Use balance (close balance room doors, use shields) (e) Volume of H 2 O 2 store-bought solution analyzed (mL) Use balance to take the mass of a certain volume of this solution. Plug into “h” (f) V: Volume of gas collected (L) [Measured After Reaction] in 100mL graduated cylinder (g) Height of water remaining in 100mL graduated cylinder above the surface level in the clear shoe box (mmH 2 O) [Measured After Reaction] use ruler for height of column from water surface to gas level Arizona State University School of Molecular Sciences 2

7. Table 2: Experimental Calculations. Complete the following table with your experimental data and calculations for each of the two trials. Trial #1 Trial #2 (h) Mass of H 2 O 2 solution analyzed (g) (i) P water column : Pressure exerted by column of water (mmHg) Convert (g) to mmHg 1mmHg = 13.595mmH 2 O Not necessary (j) P O2 : Pressure of O 2 (mmHg) Because water column pressure and the water vapor pressure are insignificant, we can assume that: P O2 = P atmospheric (k) P O2 : Pressure of O 2 (atm) Convert (j) to atm; 760 mmHg = 1 atm (l) n: Actual moles of O 2 produced (mol) PV=nRT ; n = ( k ) × ( f ) 0.08206 L∙atm K ∙mol × ( a ) (m) Mass of H 2 O 2 in store-bought solution (g) 2H 2 O 2 (aq)  2H 2 O(l) + O 2 (g) Use stoichiometry to convert from mol O 2 (l) to g H 2 O 2 (n) Mass percent of H 2 O 2 in solution (%) % m = g H 2 O 2 g g H 2 O 2 × 100% = ( m ) ( h ) × 100% (o) Average mass percent H 2 O 2 in solution Complete calculations below for Trial #1, to show all the work with correct units. 8. Calculation “h”: What is the mass of your H 2 O 2 solution for Trial #1? 9. Calculation “i”: Not necessary to Calculate the pressure (in mmHg) of the water column using the height of the water (measured in mm) that you found after completion of the reaction (1mmHg=13.595mmH 2 O). Show your work. height of water ∈ 100 mL graduatedcylinder mm x 1 mmHg 13.595 mm H 2 O ❑ 10. Calculation “j”: Because waster column pressure and the water vapor pressure are insignificant, we can assume that: P O 2 = P atmospheric P O2 = “c” 11. Calculation “k”: Convert to mmHg to atm before continuing with the next steps. (Hint: 1atm=760mmHg). Show your work. Arizona State University School of Molecular Sciences 3

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version

Access to all documents
Unlimited textbook solutions
24/7 expert homework help

12. Calculation “l”: Calculate the actual moles of O 2 from the ideal gas law, PV=nRT. (Equation 2). i. Show your work for the calculation. ii. What pressure value will you use? What are the units? iii. What volume will you use? What are the units? iv. What value of R will you use in the ideal gas law equation, PV=n R T? Include units. v. What T will you use? What are the units? 13. Calculation m”: Use the stoichiometry of the balanced reaction to convert the number of moles of O 2 gas present in the collection tube into grams of H 2 O 2 present in the store-bought solution. Show your work. 14. Calculations “n and o” (experimental value): Calculate the mass percent of H 2 O 2 in solution and get the average for your trials (if applicable). Show your work. massof solute massof solution x 100 = mass % of H 2 O 2 15. Calculate for % error by using 3% as the accepted value. Show your work. | accepted value − experimentalvalue accepted value | x 100 Arizona State University School of Molecular Sciences 4

16. Discuss possible errors and limitations in the procedures used in this investigation. 17. How could the equipment or conditions be improved to obtain better results? 18. Relate the experiment to outside research conducted; i.e, how are scientists using these techniques in their experiments? How can these techniques help you in possible field research? Arizona State University School of Molecular Sciences 5