Honors Chemistry
Hexane v. Water
Name:
Date:
1. Hexane and water are both covalent compounds.
Draw a Lewis structure of water, and show the appropriate dipoles.
Is water a polar or nonpolar molecule? Briefly explain why.
Draw a Lewis structure of hexane, C6H14. Show any appropriate dipoles.
Is hexane a polar or nonpolar molecule? Briefly explain why.
2. Directions
a. At the designated lab bench, you should find 2 burets and containers of water and hexane.
b. Make sure the stopcocks at the bottom of the burets are closed before proceeding.
c. Using the provided funnels, partially fill 1 buret with water and the other with hexane.
d. Charge the piece of plastic using the item of linen provided. This is similar to charging a balloon with
your hair.
e. Let a small stream of hexane out of the buret into a beaker. Bring the newly charged piece of plastic
up to the hexane and record your observations. Repeat this a few times.
f. Repeat this procedure for the water, noting any differences. Repeat this a few times.
3. Observations
Response of hexane:
Response of water:
Answer the following questions:
4. Explain why the water and hexane responded in the fashion that you observed.
5. How did the piece of plastic become charged? (think of the previous balloon example)
6. From this activity, you have determined that water is either polar or nonpolar. Think of 3 things in
everyday life that this might account for. (one example, which you shouldn’t use in your answer is that
water has a higher boiling point due to this property)
7. For the following molecules, determine if they are polar or nonpolar. Do this by drawing appropriate
Lewis structures and dipoles.
a. CCl4
b. NF3
c. CO2
d. H2S
e. XeO3
f. HBr