Chapter 4, Problem 19QP

Interpretation Introduction

Interpretation:

The number of formula units in ${\text{Cu}}_2\text{S}$ are to be calculated.

Concept Introduction:

A mole is a unit amount of substance. It relates a number of particles to molar mass.

One mole of any substance contains $6.022\times {10}^{23}$ particles. This number is constant for all the substance. One mole of an atom exhibits $6.022\times {10}^{23}$ atoms. One mole of molecules contains $6.022\times {10}^{23}$ molecules.