ACS CP ACS CP Biochemistry & Polymer Chemistry 3

Question 1

Nylon 6,6 is an example of which type of polymer?

Accepted Answer

Condensation polymer formed from a diamine and a diacid

Answer

Nylon 6,6 is a condensation (step-growth) polyamide formed by reacting hexamethylenediamine with adipic acid, releasing water as a byproduct.

Question 2

Which protein structural level describes the three-dimensional folding of a single polypeptide chain?

Accepted Answer

Tertiary structure

Answer

Tertiary structure describes the overall 3D conformation of a single polypeptide chain, stabilized by hydrophobic interactions, hydrogen bonds, ionic interactions, and disulfide bonds.

Question 3

Living polymerization techniques (ATRP, RAFT, NMP) are valued in polymer chemistry primarily because they allow:

Accepted Answer

Precise control of molecular weight, narrow PDI, and synthesis of block copolymers

Answer

Living/controlled radical polymerization techniques enable precise control of molecular weight (PDI < 1.2), chain-end functionality, and synthesis of complex architectures like block copolymers.

Question 4

Enzyme competitive inhibition is characterized by which observation on a Lineweaver-Burk double-reciprocal plot?

Accepted Answer

Different x-intercept (changed apparent Km), same y-intercept (unchanged Vmax)

Answer

Competitive inhibitors increase apparent Km (shifting x-intercept) but do not change Vmax (same y-intercept) because the inhibitor can be outcompeted by excess substrate.

Question 5

Which spectroscopic technique is most useful for determining the degree of crystallinity in a semi-crystalline polymer?

Accepted Answer

X-ray diffraction (XRD)

Answer

Wide-angle X-ray diffraction (WAXD/XRD) measures the ratio of crystalline diffraction peaks to amorphous scattering halo to determine percent crystallinity in polymers.

(ACS CP) American Chemical Society (ACS) Certified Professional Practice Test

(ACS CP) American Chemical Society (ACS) Certified Professional Practice Test

ACS CP ACS CP Biochemistry & Polymer Chemistry 3