[777888]

1a)A student set up a calorimeter using three nested polystyrene cups, 102.28g water, and a thermometer. 10.01g of unknown salt is dissolved and the initial temp. before dissolving is 22.0C, the final temp. after dissovling is 13.8C. Calculate the enthalpy change per g.
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I calculated and get 0.350kJ/g
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1b)If some heat were transferred to the air or the cups, would your calculated enthalpy of solution of the unknown salt be too high or too low? Explain.
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My Explanation 1: The energy released by water is not completely absorbed by the salt. Therefore, delta H(system) will be lower than 3506J, the calculated one and the enthalpy of solution will be lower. But I have assumed 100% heat transfer from water to salt, so the enthalpy of solution I have calculated would be too high.
My Explanation 2: More heat is transferred out of water(surroundings), to system and to air/cup, so temperature change of water is greater. q=mc(delta T). So q is greater and enthalpy of solution will also be greater. Therefore, the calculated one(3506J) is too low.
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I am really stucked...These 2 explanations keep going back and forth in my mind and I don't know which one is right and is my calculated one too high or too low...can someone help me Please? Thank you!

[Demotivator]

explanation 1 looks right at the moment.
I don't understand 2. How is more heat transferred out of water? How can temp change be greater? It is what it is.

[Demotivator]

Ok, so I think I understand 2.
More temp than normal becasue more heat than necessary for system is absorbed. But then, all of it is assumed to go into the solution system so the net result is the calc is too high (same as 1).

[777888]

Ok, so I think I understand 2.
More temp than normal becasue more heat than necessary for system is absorbed. But then, all of it is assumed to go into the solution system so the net result is the calc is too high (same as 1).

oic...thank you!
How about "if some salt is spilled as it transfers to the calorimeter, would your calculated enthalpy of solution of the unknown salt be too high or too low?"
[I would say too low, is it right?]