Chapter 12, Problem 12.131P

(a)

Interpretation Introduction

Interpretation:

The molar mass of each fraction is to be calculated.

Concept introduction:

Molar mass is defined as the summation of the masses of the atoms that are present in one mole of a particular molecule.

A polymer is a macromolecule that is formed from the covalently bonded structure of small molecules known as monomers. Polymers are of two types as follows:

1. Natural polymers

2. Synthetic polymers

The molecular mass of polymer depends upon the mass of monomer and number of monomer. The formula to calculate the molecular mass of polymer is as follows:

  $M_{\text{polymer}}=\left(M_{\text{monomer}}\right)\left(n\right)$        (1)

Here,

$M_{\text{polymer}}$ is the molar mass of the polymer.

$M_{\text{monomer}}$ is the molar mass of monomer.

$n$ is the degree of polymerization.

(b)

Interpretation Introduction

Interpretation:

The number-average molar mass of the sample is to be calculated.

Concept introduction:

The number-average molar mass is a method to determine the molar mass of the polymer. It is calculated by the average of the molecular masses of the individual monomer unit that combine to form a polymer. The formula to calculate the number-average molar mass of the sample is as follows:

  $\text{Number-average molar mass}=\frac{\text{total sum of all chains}}{\text{number of moles of chains}}$

(c)

Interpretation Introduction

Interpretation:

The weight-average molar mass of the sample of polytetra fluoroethylene is to be calculated.

Concept introduction:

The weight-average molar mass is a method to determine the molar mass of the polymer. The formula to calculate the weight-average molar mass of the sample is as follows:

  $\text{Weight-average molar mass}=\frac{{\displaystyle \sum \left(\text{Mass of fraction}\right)\left(\text{mass of fraction}\right)}}{\text{total mass of all fractions}}$