Chapter 10, Problem 9STP

Interpretation Introduction

Interpretation:

The number of atoms in $0\cdot 625\text{ moles}$ of Ge needs to be determined.

Concept introduction:

Avogadro's number is $6.022\times {10}^{23}\text{ units}\text{.}$

To make a conversion from moles to atoms / molecules, multiply the molar mass by Avogadro's number.

Answer to Problem 9STP

Correct answer is (c) $3\cdot 76\times {10}^{23}\text{ atoms}$

Explanation of Solution

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

(Avogadro's number)

Because $0\cdot 625\text{ moles}$ of Ge is there.

Multiplication of given moles with number of atoms per mole (Avogadro's number)

$=0\cdot 625\times 6\cdot 023\times {10}^{23}\text{ atoms/mol}$

= $3\cdot 76\times {10}^{23}\text{ atoms}$

Conclusion

Correct answer is (C) $3\cdot 76\times {10}^{23}\text{ atoms}$