Question

Q6. 2/2 points

(a)What are the chemical formulas for the compounds below ? Are the compounds shown

below isomers?

(b) Consider the two alkene compounds below? Which one is cis, which one is trans?

  

Q7. 3/3/3 points

(a) What are addition polymerization steps?

(b) What type of polymerization does the below reaction present?

(c) Calculate the degree of polymerization if 6,6-nylon has a molecular weight of 120,000 g/mol, two repeating unit of Nylon6,6 shown in (b).

Q8. 4 points

On the basis of the structures presented in this chapter, sketch repeat unit structures for

the following polymers: (a) polyethylene, and (b) Polytetrafluoroethylene (PTFE-Teflon)

Q9. 3/5/5-13 points

Kevlar (C14H10N2O2) is used in various applications from tires to body armor due to its high

strength-to-weight ratio. The polymer is produced from the monomers paraphenylene

diamine (C6H8N2) and terephthaloyl chloride (C8H4Cl2O2) by the following reaction:

(a) What type of polymerization does the above reaction represent?

(b) Assuming 100% efficiency, calculate the weight of terephthaloyl chloride required to

completely combine with 1 kg of paraphenylene diamine.

(c) How much Kevlar is produced?

Q10. 12 points

The following table lists molecular weight data for a polypropylene material. Compute the

following: (a) the number-average molecular weight, (b) the weight-average molecular

weight, and (c) the degree of polymerization, assuming polypropylene MW = 42.08 g/mole

Molecular Weight

Range (g/mol) xi wi

8,000–16,000 0.05 0.02

16,000–24,000 0.16 0.10

24,000–32,000 0.24 0.20

32,000–40,000 0.28 0.30

40,000–48,000 0.20 0.27

48,000–56,000 0.07 0.11

Q6. 2/2 points (a) What are the chemical formulas for the compounds below ? Are the compounds shown below isomers? н н н н н H CHỊ CHỊ H. н-с-с-с-с-с-н н—с-с-с-с-н н н н н н н н н н (b) Consider the two alkene compounds below? Which one is cis, which one is trans?

Answer 1

solution: 06 H H H H H I H C - I-u- c - I-u- ċ-c - C-H H H H H H Chemical formula: CGH 12 н I- U H сH 3 CH3 H -9 - q - -H и нин Iu I - I Chemical formula C6H14 formula but different Isomer: Compound having some molecular structural arrangement in space Above two structures are not isomers. 1 CH3 2 1 СИЗ CH₂ - -Hz H 31 Cis trans same priority same priority group on group on same side - opposite side- Cis Trans.