Chapter 16, Problem 16.13P

Interpretation Introduction

(a)

Interpretation:

The molecular weight of the chains for the given polymer is to be calculated.

Concept Introduction:

The molecular weight of a polymer is not fixed. It has a certain range under which its molecular weight falls. For a linear polymer, degree of polymerization represents the average length of the polymer. Degree of polymerization is defined as:

  $\begin{array}{c}\text{Degree of polymerization}=\frac{\text{average molecular weight of polymer}}{\text{molecular weight of repeating unit}}\\ n=\frac{{\left(\text{MW}\right)}_{\text{av}\text{.}}}{{\left(\text{MW}\right)}_{\text{repeating unit}}}\end{array}$   ....... (1)

Interpretation Introduction

(b)

Interpretation:

The number of chains in the given mass of polymer is to be calculated.

Concept Introduction:

The formula to calculate number of chains in the given mass of polymer is:

  $\text{Number of chains}=\frac{m\times N_A}{{\left(\text{MW}\right)}_{\text{av}\text{.}}}$   ....... (2)

Here, $m$ is the mass of the polymer, $N_A$ is the Avogadro's number, and ${\left(\text{MW}\right)}_{\text{av}\text{.}}$ is the average molecular mass of the polymer.