Chapter 10, Problem 92A

Interpretation Introduction

(a)

Interpretation:

The number of molecules needs to be determined in 1.35 mole of Carbon disulfide (CS₂)Concept introduction:

Representative particles can be atoms, molecules, formula units or ions, depending on the nature of the substance. The standard unit used to represent the amount of a substance is the mole, where a mole contains $6.022\times {10}^{23}$ particles.

Answer to Problem 92A

$8.13\times {10}^{23}\text{ molecules}$

Explanation of Solution

The given number of moles of carbon disulfide is 1.35 mol.

In 1 mol of any compound there are $6.022\times {10}^{23}$ molecules. Thus, number of molecules in 1.35 mol will be:

$N=n{N}_A$

Putting the values,

$\begin{array}{c}N=\left(1.35\text{ mol}\right)\left(6.022\times {10}^{23}\text{ molecules/mol}\right)\\ =8.13\times {10}^{23}\text{ molecules}\end{array}$

Interpretation Introduction

(b)

Interpretation:

The number of molecules in 0.254 mol of diarsenic disulfide needs to be determined.

Concept introduction:

Representative particles can be atoms, molecules, formula units or ions, depending on the nature of the substance. The standard unit used to represent the amount of a substance is the mole, where a mole contains $6.022\times {10}^{23}$ particles.

Answer to Problem 92A

$1.53\times {10}^{23}\text{ molecules}$

Explanation of Solution

The given number of moles of diarsenic disulfide is 0.254 mol.

In 1 mol of any compound there are $6.022\times {10}^{23}$ molecules. Thus, number of molecules in 0.254 mol will be:

$N=n{N}_A$

Putting the values,

$\begin{array}{c}N=\left(0.254\text{ mol}\right)\left(6.022\times {10}^{23}\text{ molecules/mol}\right)\\ =1.53\times {10}^{23}\text{ molecules}\end{array}$

Interpretation Introduction

(c)

Interpretation:

The number of molecules of water in 1.25 mol needs to be determined.

Concept introduction:

Representative particles can be atoms, molecules, formula units or ions, depending on the nature of the substance. The standard unit used to represent the amount of a substance is the mole, where a mole contains $6.022\times {10}^{23}$ particles.

Answer to Problem 92A

$7.53\times {10}^{23}\text{ molecules}$

Explanation of Solution

The given number of moles of water is 1.25 mol.

In 1 mol of any compound there are $6.022\times {10}^{23}$ molecules. Thus, number of molecules in 1.25 mol will be:

$N=n{N}_A$

Putting the values,

$\begin{array}{c}N=\left(1.25\text{ mol}\right)\left(6.022\times {10}^{23}\text{ molecules/mol}\right)\\ =7.53\times {10}^{23}\text{ molecules}\end{array}$

Interpretation Introduction

(d)

Interpretation:

The number of molecules of HCl in 150.0 mol needs to be determined.

Concept introduction:

Representative particles can be atoms, molecules, formula units or ions, depending on the nature of the substance. The standard unit used to represent the amount of a substance is the mole, where a mole contains $6.022\times {10}^{23}$ particles.

Answer to Problem 92A

$9.03\times {10}^{25}\text{ molecules}$

Explanation of Solution

The given number of moles of HCl is 150 mol.

In 1 mol of any compound there are $6.022\times {10}^{23}$ molecules. Thus, number of molecules in 150 mol will be:

$N=n{N}_A$

Putting the values,

$\begin{array}{c}N=\left(150\text{ mol}\right)\left(6.022\times {10}^{23}\text{ molecules/mol}\right)\\ =9.03\times {10}^{25}\text{ molecules}\end{array}$