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Using your results for Experiment 3: Measuring the Enthalpy of Fusion of Water, calculate the molar heat of fusion of ice, i.e., the number of kilojoules of heat per mole ice.

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Lab 7:9

Question 1 (8 points)
Upload your picture of your metal sample being massed.

To receive credit, your metal and the mass readout must be clearly visible in the picture, as well as a clear label with your name, the lab title (with Experiment number), and the date in clear view. This must be a single picture.

Question 1 options:

Question 2 (8 points)
Upload your picture of you heating your metal strips.

To receive credit, you must be clearly visible holding the metal strips in the picture, and it must include a clear label with your name, the lab title (with Experiment number), and the date in clear view. This must be a single picture.

Question 2 options:

Question 3 (8 points)
Upload your picture of your assembled calorimeter with final temperature reading.

To receive credit, your full calorimeter and temperature reading must be clearly visible in the picture, as well as a clear label with your name, the lab title (with Experiment number), and the date in clear view. This must be a single picture.

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Question 4 (20 points)
Upload your picture of your Table 2: Specific Heat Data from Experiment 1: Determination of Specific Heat of a Metal.

Question 4 options:

Question 5 (8 points)
Upload your picture of your spoonful of ammonium nitrate being transferred to your calorimeter.

To receive credit, your calorimeter and the ammonium nitrate must be clearly visible in the picture, as well as a clear label with your name, the lab title (with Experiment number), and the date in clear view. This must be a single picture.

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Question 6 (8 points)
Upload your picture of your Table 4: Cold Pack Data and Table 5: Hand Warmer Data from Experiment 2: Cold Packs vs. Hand Warmers.

Question 6 options:

Question 7 (8 points)
In Experiment 2: Cold Packs vs. Hand Warmers, according to your experimental results:

1) Calculate the overall temperature change for the cold pack, ΔT = Tmax – Tmin

2) Explain why this reaction is considered endothermic.

Show all work and be detailed in your response in order to receive credit.

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Question 8 (8 points)
Upload your picture of your Table 5: Enthalpy Data from Experiment 3: Measuring the Enthalpy of Fusion of Water.

Question 8 options:

Question 9 (8 points)
Calculate the heat lost by the hot water using your results for Experiment 3: Measuring the Enthalpy of Fusion of Water. Heat must be expressed in kilojoules (kJ).

Q= (4.18 J/g °C) x (1 kJ/1000 J) x mass of water (g) x ΔT

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Question 10 (8 points)
Using your results for Experiment 3: Measuring the Enthalpy of Fusion of Water, calculate the molar heat of fusion of ice, i.e., the number of kilojoules of heat per mole ice.

q = ΔHfusm

Question 10 options:

Question 11 (4 points)
Using your results for Experiment 3: Measuring the Enthalpy of Fusion of Water, calculate the percent error in your determination of the value for the molar heat of fusion of ice.

Percent Error = |Experimental – Actual|/ (Actual) x 100 = % Error

Question 11 options:

Question 12 (4 points)
Answer the following Post-Lab Questions on potential sources of error in this experiment.

1) What could have or did go wrong?

2) How might this have impacted your data?

3) How could you address/fix such errors in future experiments?