Chapter 4, Problem 4.8P

Interpretation Introduction

(a)

Interpretation:

The density of the given sample lead (Pb) is to be determined.

Concept introduction:

The relationship between the theoretical density $\left(\rho \right)$ of an element, number of atoms $\left(n\right)$ present in a unit cell and volume of a unit cell $\left(V\right)$ is:

  $\rho =\frac{n\times \left(\text{A}\text{.M}\right)}{V\times N_{\text{A}}}$ ........ (1)

Here, $\left(\text{A}\text{.M}\right)$ is the atomic mass of the element and $N_{\text{A}}$ is the Avogadro's number.

Volume of a unit cell $\left(V\right)$ is calculated using the lattice parameter $\left(a_0\right)$ as:

  $V={\left(a_0\right)}^3$ ........ (2)

Interpretation Introduction

(b)

Interpretation:

The number of vacancies per gram of lead is to be calculated for the given sample.

Concept introduction:

Density $\left(\rho \right)$ of a material is calculated by the formula:

  $\rho =\frac{m}{V}$ ........ (3)

Here, $m$ is the mass of the material and $V$ is the volume of the material.