Chapter 3, Problem 3.120P

(a)

Interpretation Introduction

Interpretation:

The larger quantity between $0.4\text{ mol}$ of ${\text{O}}_3\text{ molecules}$ and $0.4\text{ mol}$ of $\text{O atoms}$ is to be identified.

Concept introduction:

$1\text{ mol}$ of any substance contains Avogadro’s number of entities that is $6.022\times {10}^{23}$.

The formula to calculate the number of moles is:

  $\text{Number of moles}=\frac{\text{given mass of sample}\left(\text{g}\right)}{\text{molar mass (g/mol)}}$        (1)

The formula to calculate mass is as follows:

  $\text{Mass of a given sample}\left(\text{g}\right)=\left(\text{molar mass g/mol}\right)\left(\text{number of moles}\right)$        (2)

(b)

Interpretation Introduction

Interpretation:

The larger of the two given quantities in terms of grams is to be identified.

Concept introduction:

$1\text{ mol}$ of any substance contains Avogadro’s number of entities that is $6.022\times {10}^{23}$.

The formula to calculate the number of moles is:

  $\text{Number of moles}=\frac{\text{given mass of sample}\left(\text{g}\right)}{\text{molar mass (g/mol)}}$        (1)

The formula to calculate mass is as follows:

  $\text{Mass of a given sample}\left(\text{g}\right)=\left(\text{molar mass g/mol}\right)\left(\text{number of moles}\right)$        (2)

(c)

Interpretation Introduction

Interpretation:

Whether the number of moles will be larger in $4.0{\text{ g N}}_{\text{2}}{\text{O}}_{\text{4}}$ or $3.2{\text{ g SO}}_2$ is to be determined.

Concept introduction:

The formula to calculate the number of moles is:

  $\text{Number of moles}=\frac{\text{given mass of sample}\left(\text{g}\right)}{\text{molar mass (g/mol)}}$        (1)

The formula to calculate mass is as follows:

  $\text{Mass of a given sample}\left(\text{g}\right)=\left(\text{molar mass g/mol}\right)\left(\text{number of moles}\right)$        (2)

(d)

Interpretation Introduction

Interpretation:

Whether the mass of $0.6{\text{ mol C}}_{\text{2}}{\text{H}}_{\text{4}}$ or $0.6{\text{ mol F}}_2$ is larger is to be determined.

Concept introduction:

The formula to calculate the number of moles is:

  $\text{Number of moles}=\frac{\text{given mass of sample}\left(\text{g}\right)}{\text{molar mass (g/mol)}}$        (1)

The formula to calculate mass is as follows:

  $\text{Mass of a given sample}\left(\text{g}\right)=\left(\text{molar mass g/mol}\right)\left(\text{number of moles}\right)$        (2)

(e)

Interpretation Introduction

Interpretation:

Whether the number of ions in $\text{2}{\text{.3 mol NaClO}}_3$ or $\text{2}{\text{.2 mol MgCl}}_2$ is larger is to be determined.

Concept introduction:

The electrolyte is the substance that produces ions when it is dissolved in a polar solvent. It breaks into positively and negatively charged ions that spread uniformly through the solvent. The electrolytic solution, as a whole, is electrically neutral. Sodium chloride, potassium chloride, calcium phosphate are some of the examples of electrolytes.

Strong electrolytes are those electrolytes that completely dissociates into its ions. These have a very high value of electrical conductance. Sodium chloride and potassium chloride are strong electrolytes.

Weak electrolytes are those electrolytes that partially dissociates into its ions. They are poor conductors of electricity. Acetic acid and carbonic acid are weak electrolytes.

(f)

Interpretation Introduction

Interpretation:

Whether the number of molecules in $1.0{\text{ g H}}_{\text{2}}\text{O}$ or $1.0{\text{ g H}}_{\text{2}}{\text{O}}_2$ is larger is to be determined.

Concept introduction:

The formula to calculate the number of molecules from the number of moles is as follows:

  $\text{Number}\text{of molecules }=\left[\begin{array}{l}\left(\text{number of moles }\right)\\ \left(6.022\times {10}^{23}\text{molecules}\right)\end{array}\right]$        (3)

(g)

Interpretation Introduction

Interpretation:

Whether the mass of $6.022\times {10}^{23}{\text{atoms }}^{235}\text{U}$ or $6.022\times {10}^{23}{\text{atoms }}^{238}\text{U}$ is larger is to be determined.

Concept introduction:

$1\text{ mol}$ of any substance contains Avogadro’s number of entities that is $6.022\times {10}^{23}$.

The formula to calculate the number of moles is:

  $\text{Number of moles}=\frac{\text{given mass of sample}\left(\text{g}\right)}{\text{molar mass (g/mol)}}$        (1)

The formula to calculate mass is as follows:

  $\text{Mass of a given sample}\left(\text{g}\right)=\left(\text{molar mass g/mol}\right)\left(\text{number of moles}\right)$        (2)

The formula to calculate the number of molecules is as follows:

  $\text{Number}\text{of molecules }=\left[\begin{array}{l}\left(\text{number of moles }\right)\\ \left(6.022\times {10}^{23}\text{molecules}\right)\end{array}\right]$        (3)