Chapter 3, Problem 1CQ

To determine

To fill:

The correct term in the given blank.

Introduction:

Ruby is a very precious gemstone. The ruby found in different colors. The value of a ruby is determined by its color and cut. There are some impurities always present in ruby.

Answer to Problem 1CQ

The red color of ruby is obtained from the substitution of chromium atoms for the atoms of aluminum in a crystal of ${\text{Al}}_{\text{2}}{\text{O}}_{\text{3}}$.

Explanation of Solution

In the crystal of iron, when an iron atom is substituted by nickel atom then the structure is known as a substitutional solid solution.

Now, in the crystal of ${\text{Al}}_{\text{2}}{\text{O}}_{\text{3}}$, when an aluminum atom is substituted by chromium atom, it produces Ruby’s red color.

Thus, the red color of ruby is obtained from the substitution of chromium atoms for the atoms of aluminum in a crystal of ${\text{Al}}_{\text{2}}{\text{O}}_{\text{3}}$.