I'll also revive this thread!
A new polymer is being tested for use as a a lightweight rain jacket.
a. Given that the empirical formula of this compound is (completely made up, not real) CH3N, what types of attractive forces would you expect molecules of this polymer to exhibit?
b. In a laboratory, water is dropped onto a 1 cm x 1 cm square of the material. Water is added to the droplet in order to determine the maximum and minimum contact angles. Because the two angles are very similar, the contact angle is simplified to be 60°. Would you recommend this material for its intended use? Explain.
c. Name the test used above to determine contact angle, and give another test that can be used to achieve the same purpose.
Um, I'm really not quite sure but here goes:
a) I think there would be covalent bonding in between the carbon and the nitrogen, but also maybe some hydrogen bonding occuring between the nitrogen and the hydrogen.
b) Not completely, since I would expect an angle of 90 degrees or more to be ideal for use on a rain jacket. The whole purpose of the rain jacket is to repel rain, not absorb it. The contact angle is the wetability, so if the angle is about 60 I think that would be alright but preferrably something with an angle of 90 degrees or more.
c) Contact angle hystersis? Another test I can think of would be the Wilhelmy plate method which measures the tensile forces of the droplet in which it is put onto.
End of freshman season. Good luck to everyone! No state for us, but nevertheless great season. Regional was out of 12 teams. (CLC)
Mat Sci-> Second at regionals
RSensing -> First at regionals
Towers-> Third at regionals.