Chapter 10, Problem 111A

Complete Table 10.3.

Interpretation Introduction

Interpretation: The mass and number of particles in 3.65 moles of magnesium needs to be determined.

Concept Introduction: The mole concept provides the relation between moles, mass and molar mass. The mathematical expression of mole concept can be written as:

  $\text{Mole =}\frac{\text{Mass}}{\text{Molar mass}}$

1 mole of any substance contains $\text{6}\text{.022 }\times {\text{ 10}}^{\text{23}}$ number of particles or atoms or molecules.

Answer to Problem 111A

$\text{22}{\text{.0× 10}}^{\text{23}}\text{atoms}$ and $\text{87}\text{.6 g}$

Explanation of Solution

Moles given = 3.65 moles

Molar mass of Mg = 24.0 g/mol

1 mole = $\text{6}\text{.022 }\times {\text{ 10}}^{\text{23}}$ atoms

Calculate number of atoms:

  $\text{3}\text{.65 moles ×}\frac{\text{6}{\text{.022 × 10}}^{\text{23}}\text{atoms}}{\text{1 mole }}\text{= 22}{\text{.0× 10}}^{\text{23}}\text{atoms}$

Calculate mass:

  $\text{3}\text{.65 moles ×}\frac{\text{24}\text{.0 g}}{\text{1 mole }}\text{= 87}\text{.6 g}$

Interpretation Introduction

Interpretation: The moles and number of particles in 29.54 g of Chromium needs to be determined.

Concept Introduction: The mole concept provides the relation between moles, mass and molar mass. The mathematical expression of mole concept can be written as:

  $\text{Mole =}\frac{\text{Mass}}{\text{Molar mass}}$

1 mole of any substance contains $\text{6}\text{.022 }\times {\text{ 10}}^{\text{23}}$ number of particles or atoms or molecules.

Answer to Problem 111A

$\text{3}{\text{.42× 10}}^{\text{23}}\text{atoms}$ and $\text{0}\text{.568 moles}$

Explanation of Solution

Mass of Cr = 29.54 g

Molar mass of Cr = 52.0 g/mol

1 mole = $\text{6}\text{.022 }\times {\text{ 10}}^{\text{23}}$ atoms

Calculate moles:

  $\text{29}\text{.54 g ×}\frac{\text{1 mole }}{\text{52}\text{.0 g }}\text{= 0}\text{.568 moles}$

Calculate number of atoms:

  $\text{0}\text{.568 moles ×}\frac{\text{6}{\text{.022 × 10}}^{\text{23}}\text{atoms}}{\text{1 mole }}\text{= 3}{\text{.42× 10}}^{\text{23}}\text{atoms}$

Interpretation Introduction

Interpretation: The mass and number of particles in 0.568 moles of Arsenic needs to be determined.

Concept Introduction: The mole concept provides the relation between moles, mass and molar mass. The mathematical expression of mole concept can be written as:

  $\text{Mole =}\frac{\text{Mass}}{\text{Molar mass}}$

1 mole of any substance contains $\text{6}\text{.022 }\times {\text{ 10}}^{\text{23}}$ number of particles or atoms or molecules.

Answer to Problem 111A

$\text{ 3}{\text{.42× 10}}^{\text{23}}\text{atoms}$ and $\text{42}\text{.5 g}$

Explanation of Solution

Moles given = 0.568 moles

Molar mass of As= 74.9 g/mol

1 mole = $\text{6}\text{.022 }\times {\text{ 10}}^{\text{23}}$ atoms

Calculate number of atoms:

  $\text{0}\text{.568 moles ×}\frac{\text{6}{\text{.022 × 10}}^{\text{23}}\text{atoms}}{\text{1 mole }}\text{= 3}{\text{.42× 10}}^{\text{23}}\text{atoms}$

Calculate mass:

  $\text{0}\text{.568 moles ×}\frac{\text{74}\text{.9 g}}{\text{1 mole }}\text{= 42}\text{.5 g}$