Last modified: Mon 09/16/2013 10:18:15 pm
ACA

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Answer all of the questions below. If you do not know an answer enter CNA. However, it will help me the most if you answer each question with your best intuition/idea about what would be a reasonable answer.


First Name:

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Laboratory Section:

1. A solution is prepared by mixing 3.00 grams of NaCl with 125.0 grams of H2O.

a) Calculate the mol of sodium chloride that are dissolved in water.

mol NaCl

b) Calculate the molality (sodium chloride) of the solution.

molal

c) Is sodium chloride an electrolyte or a nonelectrolyte when dissolved in water?

d) Calculate the ideal freezing point of this solution. (NOTE: k f(H2O) = 1.86 °C m-1)

°C

e) Calculate the ideal boiling point of this solution. (NOTE: kb(H2O) = 0.512 °C m-1)

°C

2. A solution is prepared by mixing 0.72 grams of Li2CO3 in 100. grams of H2O. Calculate the ideal freezing point and the ideal boiling point of the solution. (NOTE: k f(H2O) = 1.86 C m-1 and kb(H2O) = 0.512 )

°C (freezing point)

°C (boiling point)

3. Calculate the molar mass of nicotine if 5.04 grams of this compound changes the freezing point of 90.0 gram of water by 0.647 °C.

g mol-1

4. Is there anything about the questions that you feel you do not understand? List your concerns/questions.

5. If there is one question you would like to have answered in lecture, what would that question be?