Friday, November 17, 2006
AP Lab "Critical Thinking" Question 1
This came up at extra help on Friday: I should have written the first "Critical Thinking" question a bit differently. If you have already done that question, you don't have to change your answer but, if you haven't done "Critical Thinking" Question 1 yet, just change it to the following:
Assume that there were some water droplets on the evaporating dish; since the water droplets contribute to the mass of the evaporating dish, for THIS question, CHANGE the combined mass of the evaporating dish and Zinc to a value GREATER than 41.11 grams (because the water droplets contribute mass to the dish but assume that you used the SAME amount of Zinc as in the original data...remember, you didn't SEE the tiny water droplets in or on the dish BUT they will be vaporized away during the evaporation process). Then, do the rest of the calculation to see whether the empirical formula of zinc chloride obtained is the same as or different from what you got by using the correct lab procedure data.
Any questions, email me.
Sorry for the mix-up. How about this? You can hand the lab in on Tuesday! Better times.
Assume that there were some water droplets on the evaporating dish; since the water droplets contribute to the mass of the evaporating dish, for THIS question, CHANGE the combined mass of the evaporating dish and Zinc to a value GREATER than 41.11 grams (because the water droplets contribute mass to the dish but assume that you used the SAME amount of Zinc as in the original data...remember, you didn't SEE the tiny water droplets in or on the dish BUT they will be vaporized away during the evaporation process). Then, do the rest of the calculation to see whether the empirical formula of zinc chloride obtained is the same as or different from what you got by using the correct lab procedure data.
Any questions, email me.
Sorry for the mix-up. How about this? You can hand the lab in on Tuesday! Better times.
# posted by C @ 10:53 PM 
