At the beginning of Chapter 12 we talked about the concept of attractive forces. Attractive forces between molecule are what we believe lead to the formation of the liquid and solid phase.

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Give me some responses to the questions below and I'll give you some extra credit.

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Laboratory Section:

1. In the Pre-laboratory questions for the Survival Organic Chemistry Experiment you were asked, among other things, to indicate whether a substance was polar or not. Briefly explain how you determined the polarity of a substance.

2. For each of the following substances use your method to determine whether the substance is polar or not.

a) SO2

b) CO2

c) XeF2

d) 1,1-dichloroethane

e) pentane

Now look at the animation below.

In this animation the interaction between two water molecules will be shown. Click the mouse to start the animation. The water molecules will move to the center of the animation and pause. Begin answering the questions after the molecules stop moving.

3. There are two water molecules shown in the center of the animation, indicate which atom(s) is oxygen and which atom(s) is hydrogen. The two colors of atoms I see are bluish-green and red. (Click the mouse to continue after answering this question to resume the animation.)

4. The next time the animation pauses, indicate the partial charge (positive or negative) on each atom in the two water molecules. Use the numbered atoms to help with labeling. Do not forget which atom is hydrogen and which is oxygen. Anwer Question 5 and 6 before resuming the animation.

5. Explain how you arrived as the partial charge assignment you used in Question #4.

6. Using the numbers identify the atoms likely to participate in an attractive interaction. (Resume the animation after answering this question.)

7. Is there anything about this animation that you feel you do not understand? List your concerns/questions.