Description Make sure you understand the overall picture before you come to lab. In Part A you will ...

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Description Make sure you understand the overall picture before you come to lab. In Part A you will determine the mole mole relationship between your starting material, sodium bicarbonate ("sodium hydrogen carbonate") and the product, CO2 gas. Once you know this relationship from Part A, you will use that known relationship to analyze the amount of sodium bicarbonate in an antacid. (The label claims 1.916 g NaHCO3 per tablet.) Check with me before you move onto Part B so I can make sure you have the correct reaction! Below I show a diagram of how to arrange your reactants so you can weigh the correct values: In Part B, you will use the balanced reaction you picked from your data in Part A, along with the moles of CO2 produced, to determine how many moles of sodium bicarbonate are in the antacid tablet. (This relationship will come in at lines (e) and (f) of the table in Part B.) When you add sodium bicarbonate to the acid, add slowly. If the mixture bubbles over the beaker and loses liquid, you will need to start over. Also note that if the bicarbonate spills outside of the beaker, this will also cause significant error in the results. Complete calculations from Part A and have me check your reaction (sign your notebook) before moving on. Only then may you obtain the antacid. Antacid contains some insoluble binding agents to help hold the pill shape. That means there will be some white junk in your reaction for Part B even after it has gone to completion. After you have completed the pre-lab calculation and understand how the procedure works, watch the videos for Part A. Complete the calculations during our lab period and make sure you have the correct results before moving on to Part B. Your results in Part B depend on your results from Part A so ask for help and check with me before moving on to Part B! (I normally only hand out the Alka Seltzer after you have selected and written your reactions for Part A.) Videos for this lab are located on my youtube channel, Stoichiometry Playlist: https://www.youtube.com/playlist?list=PLuuIip6svThbeLGRRsfXq_NCErDVXH1Qm [+] prelab lecture: https://www.youtube.com/watch?v=cG3wmygIAok&list=PLuuIip6svThbeLGRRsfXq_NCErDVXH1Qm&index=1&t=699s [+] Question 1:Results Part A: Reaction Stoichiometry of Sodium Bicarbonate with Acetic Acid. Enter the results for Part A, based on the masses determined in the lab video for Part A. Although your data may not be rounded, round the answers for the results below to the appropriate number of significant figures. Trial 1 Trial 2 Trial 3 mass of CO2 gas released g g g moles of CO2 gas released mol mol mol moles of CO2 gas, corrected for amount dissolved mol mol mol moles of NaHCO3 used mol mol mol Using the results above, select the reaction that best described the chemical reaction between sodium bicarbonate and acetic acid. (Note that the order may not match the lab manual, so check each reaction carefully.) NaHCO3(s) + HC2H3O2(aq) ? CO2(g) + H2O(l) + NaC2H3O2(aq) 2 NaHCO3(s) + HC2H3O2(aq) ? CO2(g) + Na2CO3(aq) + H2O(l) + 2 CH2O(aq) NaHCO3(s) + HC2H3O2(aq) ? 2 CO2(g) + CH3OH(aq) + NaH(aq) Question 2:Results Part B: Analysis of an Antacid Enter the results for Part B, based on the masses determined in the lab video for Part B. Round all answers below to 2 significant figures. (Trial 2 produced only one significant figure, but we will use 2 sig figs in this section.) Trial 1 Trial 2 mass of CO2 gas released g g moles of CO2 gas released mol mol moles of CO2 gas, corrected for amount dissolved mol mol Experimental moles of NaHCO3 mol mol Experimental mass of NaHCO3 g g Average mass of NaHCO3 for two tablets: g Question 3:Describe how your data in Part A supports your conclusion about the appropriate reaction in Part A. Question 4:In Part B, suppose some of your reaction mixture splashed out of the beaker when you dropped the tablets into the acetic acid. How would this affect your measurements? Be as specific as possible. How would the splashing error affect the amount of CO2 determined, and consequently, would your final calculated mass of sodium bicarbonate in the tablet be artificially high or artificially low? Question 5:To calculate the percent error, use the mass of sodium bicarbonate in one tablet of Alka-Seltzer recorded from the package for the true value and your average mass of NaHCO3 for the experimental value. (Show 1 significant figure) %