Question

Can someone help me, please?
Organic, Biological, and Nuclear Chemistry.

4. A plastic substance is reheated but won't soften enough to be remolded. This substance must be a
A. thermosetting polymer.
B. thermoplastic material.
C. natural polymer.
D. synthetic monomer.

5. Vitamins are classified according to
A. their coenzymes.
B. their functions in the body.
C. their solubility in water and fat.
D. their ability to fight disease.

Answer 1

4. See page 658. Other plastics harden permanently when molded. Because they are set permanently in the shape they first form, there are called thermosetting polymers. No matter how much they are reheated, they wont soften enough to get remolded.

So the answer is "A - Thermosetting Polymer"

Answer 2

#4 The answer is A. thermosetting polymer.

#5 Thee answer is C. their solubility in water and fat.