Chapter 4, Problem 4.7P

Interpretation Introduction

(a)

Interpretation:

The number of vacancies in lithium per cubic centimeters at given conditions is to be determined.

Concept introduction:

The number of vacancies per ${\text{cm}}^3$ is calculated by the formula;

  $n_v=\frac{\text{number of vacancies in unit cell}}{V}$ ...... (1)

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 density of the given sample lithium 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:

  $\rho =\frac{n\times \left(\text{A}\text{.M}\right)}{V\times N_{\text{A}}}$ ...... (3)

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