Chapter 8.1, Problem 9SSC

Interpretation Introduction

Interpretation:

The conversion factor that used to convert between particles and moles needs to be explained.

Concept introduction:

In 1 mol of any substance, there are $6\cdot 023\times {10}^{23}\text{ particles}$ which is known as Avogadro’s law.

Answer to Problem 9SSC

Avogadro's number:

$1\text{ mole = }6\cdot 023\times {10}^{23}\text{ particles}$ (atoms, molecules etc.)

To convert moles to particles, multiply the molar amount by Avogadro's number. Also, to convert atoms/particles to moles, divide the particles/atoms by Avogadro's number.

Explanation of Solution

$\begin{array}{l}1\text{ mol}=6\cdot 023\times {10}^{23}\text{ particles}\\ \left(\text{atoms/molecules/ions etc}\text{.}\right)\\ \frac{\text{1 mol}}{6\cdot 023\times {10}^{23}\text{ particles}}\end{array}$

as well as $\frac{6\cdot 023\times {10}^{23}\text{ particles}}{\text{1 mol}}$

or

One mole of a substance $\left(6\cdot 023\times {10}^{23}\text{ molecules}\right)$ has the same mass in grams of the molar mass of the substance.

Conclusion

Thus,

Avogadro’s number as a conversion factor,

$\frac{\text{1 mol}}{6\cdot 023\times {10}^{23}\text{ particles}}$ or

$\frac{6\cdot 023\times {10}^{23}\text{ particles}}{1\text{ mole}}$