Chapter 3, Problem 41QP

Interpretation Introduction

Interpretation:

The number of atoms present in $25.85\text{ g of Cu}$ is to be determined.

Concept Introduction:

The molar mass of the substance is the mass of that substance present in one mole of it.

A mole is a quantity used to express a very large number of atoms or molecules. One mole of a substance is equal to $6.022\times {10}^{23}$, that is, Avogadro’s number.

The moles of a substance are expressed as $n=\frac{m}{\text{M}}$

Here, $m$ is the mass of the substance, M is the molar mass, and $n$ is the number of moles.

The mass of a substance is given by the expression $m=\text{M}n$

The relationship between moles of a substance and number of atoms can be expressed as $1\text{ mole = 6}\text{.022}\times {\text{10}}^{23}\text{atoms}$

To convert moles into number of atoms, conversion factor is $\frac{6.022\times {10}^{23}\text{ atoms}}{1\text{ mol}}$.