Spring 2023 CHEM 120 Determination of Equilibrium Constants Post Lab Questions M Th Make sure that your responses to these discussion questions is legible if your responses are illegible they will not receive credit We suggest that you type your responses Using the data that you collected and wrote in your lab notebook during lab organize your data into the required tables or graphs Make sure that you format the table properly i e include a title and labels for your columns etc Also make sure your plots are properly formatted and clearly labeled 1 In a table compile the FeSCN2 for the serial dilutions and the associated absorbance values Please make sure to include all proper labels and units 2 points Table 1 Absorbance of Serial Dilutions Absorbance 470nm FeSCN2 0 0020 M 0 0010 M 0 0005 M 0 00025 M 0 696 0 319 0 152 0 047 2 In a second table tabulate the absorbance values for the trial solutions with the volumes of 0 0020 M Fe NO3 3 and 0 0020 M KSCN used Please include all proper labels and units 2 points Table 2 Absorbance for Trial Solutions Sample 0 0020M Fe NO3 3 mL 0 0020 M KSCN mL Absorbance 470nm 9 00 8 00 7 00 6 00 5 00 4 00 3 00 2 00 1 00 1 00 2 00 3 00 4 00 5 00 6 00 7 00 8 00 9 00 0 127 0 197 0 281 0 310 0 348 0 405 0 423 0 394 0 168 1 2 3 4 5 6 7 8 9 3 During lab a student observed a darkening of the color in the temperature solution when placed in an ice water bath Based on these observations A Is the reaction Fe3 aq SCN aq FeSCN2 aq endothermic or exothermic B What would happen to the average value of K if the experiment were performed at a a The reaction was Exothermic higher ambient temperature 3 points a It would be a lower K value and cause a lower absorbance since the reaction is Exothermic 4 What changes did you observe in your NaCl and NaH2PO4 solutions when you added the reagents Based on your observation does the addition of these reagents shift the equilibrium to the reactants side or the products side 3 points a The changed that were observed were change in color when the NaCl was added the color slowly lighter When the NaH2PO4 was added the color also changed but instantly this time With the addition of these reagents the equilibrium was shifted to the side of the products