chemical reactions
(3pts) “UTA CHEM 1451-Experiment 5: Chemical Reactions”
Are you completing this experiment online?Yes
Data Sheet (3pts)
Data Table: Mass Measurements for Each Reaction Run Mass of citric acid (g)(a) Mass of beaker, citric acid solution, and stirring rod BEFORE reaction (g)(b) Mass of sodium bicarbonate (g)(c) Mass of beaker, solution, and stirring rod AFTER reaction is complete (g)Reaction 11.51119.370.67119.69Reaction 21.49117.021.31117.69Reaction 31.50115.991.97116.95Reaction 41.51116.262.63117.89Reaction 51.50117.293.29119.53
(11pts) Determining the Mass Lost During the Reaction
Be sure to show all your work and use the correct number of significant figures and units.
1. Complete the following table.
Table view List viewDetermining the Mass Lost During the Reaction (a) Mass of beaker, citric acid solution, and stirring rod BEFORE reaction (g)(b) Mass of sodium bicarbonate (g)(a+b) Total mass BEFORE reaction (g)(c) Total mass AFTER reaction (g)Mass lost during reaction (g)Reaction 1119.370.67119.69Reaction 2117.021.31117.69Reaction 3115.991.97116.95Reaction 4116.262.63117.89Reaction 5117.293.29119.53(1pts)For full credit, upload an image of ALL your calculations for question 1.
Maximum size for new files20.00MB
Maximum attachments5
cloud_upload
Drag and drop a file or folder here or click
(34pts) Determining the mole-to-mole ratio
Because we are working with relatively small amounts of substances, we will calculate amounts in millimoles (mmol) instead of moles, where 1 mmol = 1×10-3 mol
2. Complete the following table, referring to the data table and question 1 as necessary. You will then plot the data in this table to determine the mole-to-mole ratio. Be sure to enter the amount of sodium bicarbonate in millimoles.
Table view List viewDetermining the mole-to-mole ratio Mass of carbon dioxide produced (g)Amount of of sodium bicarbonate (mmol)No reaction0.000.0Reaction 1Reaction 2Reaction 3Reaction 4Reaction 5(1pts)For full credit, upload an image of ALL your calculations for the table in question 2.
Maximum size for new files20.00MB
Maximum attachments5
cloud_upload
Drag and drop a file or folder here or click
Using the data in the table above and a program like Excel, make a plot of “mass of carbon dioxide produced” vs “mmol sodium bicarbonate” including the 0,0 data point. The plot should have two distinct portions, an increasing portion on the left and a flat portion on the right. The mole-to-mole ratio will be determined from the intersection of the two lines.
You will need to generate a trendline for each portion of the plot. In order to do this, you will need to identify at the transition point where the graph stops increasing and starts to flatten. Then generate a trendline for the left, increasing portion including the transition point and a trendline for the right, flat portion including the transition point. Record the slopes and y-intercepts of each trendline in the table below.
(0pts)Which reaction run is the transition point between the left, increasing portion and the right, flat portion?Choose…Reaction 2Reaction 3Reaction 4Table view List viewTrendlines for plot of “mass of carbon dioxide” vs “mmol of sodium bicarbonate” Slopey-InterceptLeft, increasing portionRight, flat portion(2pts)
Upload your graph here. Be sure to show the trendline equations on your graph. A proper graph should fill a normal sheet of paper, have a title and labeled axes. The axes should be expanded to fit the range of your data (and not more). You can upload your graph directly (as a .xlsx, .csv, or .txt file) or upload a screen shot or photo of your graph (as a .pdf, .jpg, .png, or .heic file).
Note: Hand drawn graphs are not accepted.
Maximum size for new files20.00MB
Maximum attachments5
cloud_upload
Drag and drop a file or folder here or click
3. Locate the point where you determined that the graph transitioned from increasing on the left and (where the amount of CO2 produced was increasing) and the flat on the right (where the amount of CO2 produced was constant) and determine the mmol of sodium bicarbonate at this interaction.
(2pts)mmol of sodium bicarbonate at transition point:
4. Calculate the number of millimoles of citric acid that were used in this reaction run. Refer to the data table to find the actual mass of citric acid that was used in this reaction run.
(2pts)mmol of citric acid:(1pts)For full credit, upload an image of ALL your calculations for question 4.
Maximum size for new files20.00MB
Maximum attachments5
cloud_upload
Drag and drop a file or folder here or click
5. Calculate the mole-to-mole ratio between sodium bicarbonate and citric acid according to your data. Remember mole-to-mole ratios are always small whole number ratios like 2:1, 3:2, etc.
Find the mole-to-mole ratio using the following equation:
mmol sodium bicabonatemmol citric acidmmol sodium bicabonatemmol citric acid
Report your mole to mole ratio as the number of moles of sodium bicarbonate per one citric acid and round to a whole number. For example a ratio of 2:1 would be reported as 2.
(2pts)mole sodium bicarbonte per 1 mol citric acid:
rounded to a whole number(1pts)For full credit, upload an image of ALL your calculations for question 5.
Maximum size for new files20.00MB
Maximum attachments5
cloud_upload
Drag and drop a file or folder here or click
(52pts) Questions
(5pts)
6. The reaction of citric acid and sodium bicarbonate produces sodium citrate and water in addition to the carbon dioxide. Balance the following reaction equation:
Saved
→attachment
(5pts)
7. Does your experimentally determined mole-to-mole ratio match the equation you balanced above? Explain.
→attachment
8. Look at your graph and choose one of the reaction runs from the left, increasing portion of your graph. Then answer the following questions for that reaction run.
(0pts)Reaction run number:Choose…Reaction 1Reaction 2
a. Determine the limiting reagent for this reaction by calculating the moles of carbon dioxide that can be formed from each reagent. Refer to the data table for the actual masses of citric acid and sodium bicarbonate that were used for the reaction run that you selected.
(2pts)Moles of CO2 that can be produced from citric acid:(2pts)Moles of CO2 that can be produced from sodium bicarbonate:(1pts)Limiting reagent:Choose…citric acidsodium bicarbonate
b. Calculate the theoretical yield of carbon dioxide in grams using the moles of carbon dioxide that can be produced from the limiting reactant as calculated above in part a.
(5pts)Theoretical yield of CO2 in grams:
c. Calculate the percent yield of carbon dioxide using the actual yield of carbon dioxide in grams from question 2 and the theoretical yield of carbon dioxide in grams as calculated above in part b.
(5pts)Percent yield of CO2:(1pts)
For full credit, upload an image of ALL your work for the calculations for question 8.
Maximum size for new files20.00MB
Maximum attachments5
cloud_upload
Drag and drop a file or folder here or click
9. Look at your graph and choose one of the reaction runs from the right, decreasing portion of your graph. Then answer the following questions for that reaction run.
(0pts)Reaction run number:Choose…Reaction 4Reaction 5
a. Determine the limiting reagent for this reaction by calculating the moles of carbon dioxide that can be formed from each reagent. Refer to the data table for the actual masses of citric acid and sodium bicarbonate that were used for the reaction run that you selected.
(2pts)Moles of CO2 that can be produced from citric acid:(2pts)Moles of CO2 that can be produced from sodium bicarbonate:(1pts)Limiting reagent:Choose…citric acidsodium bicarbonate
b. Calculate the theoretical yield of carbon dioxide in grams using the moles of carbon dioxide that can be produced from the limiting reactant as calculated above in part a.
(5pts)Theoretical yield of CO2 in grams:
c. Calculate the percent yield of carbon dioxide using the actual yield of carbon dioxide in grams from question 2 and the theoretical yield of carbon dioxide in grams as calculated above in part b.
(5pts)Percent yield of CO2:(1pts)
For full credit, upload an image of ALL your work for the calculations for question 9.
Maximum size for new files20.00MB
Maximum attachments5
cloud_upload
Drag and drop a file or folder here or click
(5pts)
10. Most commercial instant sparkling drink tablets or powders found in grocery stores use the combination of citric acid and sodium bicarbonate. Find an example of such a drink tablet or powder. Write all the ingredients listed on the package.
→attachment
(5pts)
11. Explain why the combination of citric acid and sodium bicarbonate in these drink tablets or powders so not react until you dissolve them in water.
→attachment
Total: -/100 pts
SUBMIT
