Chapter 10.1, Problem 13SSC

Interpretation Introduction

Interpretation:

The number of representative particles needs to be determined in 11.5 mol of Ag.

Concept introduction:

In 1 mol of any substance, there are $6.022\times {10}^{23}$ units of that substance. These units can be atoms and molecules. The number of units in 1 mol of any substance is known as Avogadro’s number. It is denoted by symbol N_A.

Answer to Problem 13SSC

$6.926\times {10}^{24}$atoms.

Explanation of Solution

For the given moles of an element, the number of atoms can be calculated using the following formula:

$N=n{N}_A$

Putting the values,

$\begin{array}{l}N=\left(11.5\text{ mol}\right)\left(6.022\times {10}^{23}\right)\\ =6.925\times {10}^{24}\text{ atoms}\end{array}$

Thus, the number atoms in 11.5 mol of Ag is $6.925\times {10}^{24}\text{ atoms}$.

Interpretation Introduction

Interpretation:

The number of representative particles needs to be determined in 18.0 mol of H₂O.

Concept introduction:

In 1 mol of any substance, there are $6.022\times {10}^{23}$ units of that substance. These units can be atoms and molecules. The number of units in 1 mol of any substance is known as Avogadro’s number. It is denoted by symbol N_A.

Answer to Problem 13SSC

$1.084\times {10}^{25}\text{ molecules}$.

Explanation of Solution

For the given moles of a compound, the number of molecules can be calculated using the following formula:

$N=n{N}_A$

Putting the values,

$\begin{array}{l}N=\left(\text{18}\text{.0 mol}\right)\left(6.022\times {10}^{23}\right)\\ =1.084\times {10}^{25}\text{ molecules}\end{array}$

Thus, the number molecules in 18.0 mol of H₂O is $1.084\times {10}^{25}\text{ molecules}$.

Interpretation Introduction

Interpretation:

The number of representative particles needs to be determined in 0.150 mol of NaCl needs to be determined.

Concept introduction:

In 1 mol of any substance, there are $6.022\times {10}^{23}$ units of that substance. These units can be atoms and molecules. The number of units in 1 mol of any substance is known as Avogadro’s number. It is denoted by symbol N_A.

Answer to Problem 13SSC

$9.033\times {10}^{22}\text{ molecules}$.

Explanation of Solution

For the given moles of a compound, the number of molecules can be calculated using the following formula:

$N=n{N}_A$

Putting the values,

$\begin{array}{l}N=\left(\text{0}\text{.150 mol}\right)\left(6.022\times {10}^{23}\right)\\ =9.033\times {10}^{22}\text{ molecules}\end{array}$

Thus, the number molecules in 0.150 mol of NaCl is $9.033\times {10}^{22}\text{ molecules}$.

Interpretation Introduction

Interpretation:

The number of representative particles needs to be determined in $1.35\times {10}^{-2}\text{ mol}$ mol of CH₄.

Concept introduction:

In 1 mol of any substance, there are $6.022\times {10}^{23}$ units of that substance. These units can be atoms and molecules. The number of units in 1 mol of any substance is known as Avogadro’s number. It is denoted by symbol N_A.

Answer to Problem 13SSC

$8.13\times {10}^{21}\text{ molecules}$.

Explanation of Solution

For the given moles of a compound, the number of molecules can be calculated using the following formula:

$N=n{N}_A$

Putting the values,

$\begin{array}{l}N=\left(\text{1}\text{.35}\times {\text{10}}^{-2}\text{ mol}\right)\left(6.022\times {10}^{23}\right)\\ =8.13\times {10}^{21}\text{ molecules}\end{array}$

Thus, the number molecules in $\text{1}\text{.35}\times {\text{10}}^{-2}\text{ mol}$ of CH₄ is $8.13\times {10}^{21}\text{ molecules}$.