Things went pretty well this week. These are the points we encountered:
Part II A
- Make sure they make their solutions in the calorimeters. Some of them were pouring it in a test tube and then putting it in the calorimeter.
- Remind them to use 10 (J/g.celsius) for their calorimeter constant not the one in the sample problem.
- For MgCl2 some students ended up having graphs that had a maximum and then it leveled off. Although that is not a problem, the difference between them was too big and when they used the max for their calculations they got high numbers. I don't know the reason and thus the solution. I think that is something to talk about in the next TA meeting.
Part II B
- Remind them to use low-graded NaCl for this part.
- Using more ice and salt in their ice baths helps.
- Tell them to extend the time data is collected on Logger-Pro. They need at least 2-3 minutes.
- Tell them to ask other groups who have got a good result. It would be a good starting point.
- It seems like using the smaller test tubes helps better. Also tell them to make sure the test-tube is completely immersed in the ice bath.
Have a great week,