1. 4.5/7 points Last Response | Show Details All Responses Notes In Part A of the experiment, you tested the assumption that the contents of the styrofoam cup were isolated from the rest of universe. a. Which of the following would indicate that the Styrofoam cup is able to isolate the reaction mixture from the rest of the universe? (_) (_) qcold = qwarm (o) (o) qcold = -qwarm (_) (_) qcold > qwarm (_) (_) qcold < qwarm (_) (_) The relationship between qcold and qwarm cannot prove this. b. Enter the value you obtained for each of the following: qcold water. 0 [0.00] kJ qwarm water. 0 [0.00] kJCalculate the percent difference between these values, using the absolutevalues of the q's, and treat qcold water as the theoretical value. Report the percent difference as its absolute value. We're concerned with the size (magnitude) of the difference, not its sign. % difference between q's = 0 [ ] %. 2. 10/10 points Last Response | Show Details All Responses Notes In Part B of this experiment, you are relying on accurate mass and T measurements to determine the specific heat of the metal. You are also assuming that the Styrofoam cups isolate the system and surroundings from the rest of the universe. You checked this assumption in Part A. a. A pair of students found a 3.0% error in Part A. They now have to distinguish between Cu (specific heat = 0.384 J/g-°C) or Zn (s = 0.389 J/g-°C). They have exactly 5.00 g of the metal.What is the percent difference between the specific heats of the two metals? Usethat of Cu as the theoretical value.1.3 [1.3] %Can they use calorimetry to determine which metal they have? (_) (_) Yes (_) (_) This cannot be determined with the information given. (_) (_) It depends on the amount of water used in the calorimeter. (_) (_) It depends on how hot the metal is before it is added it to the calorimeter. (o) (o) No b. If 3.0% of the heat being measured was being lost to the universe,determine whether they could they distinguish between iron (s = 0.444 J/g-°C) and Ni (s = 0.449 J/g-°C).What is the percent difference between the specific heats of the two metals? Use that of iron as the theoretical value.1.13 [1.13] %Is this difference large enough for to differentiate between the metals? (o) (o) No (_) (_) It depends on the amount of water used in the calorimeter. (_) (_) This cannot be determined with the information given. (_) (_) Yes (_) (_) It depends on how hot the metal is before it is added it to the calorimeter. 3. 3/8 points Last Response | Show Details All Responses Notes In this exercise, you will calculate molar value of H (in kJ/mol) for dissolving NH4H2PO4 in Part D of the Calorimetry lab. a. What temperature change did you find for dissolving NH4H2PO4 in Part D of theexperiment? Be sure to include the sign, + or -! +21.2 [21.2]°Cb. What mass of water did you find in Part D of the experiment? 94.452 [94.452] gc. What mass of NH4H2PO4 did you dissolve in Part D of the experiment? 8.625 [8.625] gd. Calculate H in kilojoules for your reaction in Part D. Even though your data may not warrant it, report your answer to three significant figures! 0 [-8.38]kJe. Calculate the molar value of H (in kJ/mol) for the reaction in Part D. Again report your answer to three significant figures. 0
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