Chapter 3, Problem 3.13P

(a)

Interpretation Introduction

Interpretation:

The moles of manganese in $\text{62}\text{.0 mg}$ of $\text{Mn}$ is to be determined.

Concept introduction:

One mole is defined as the amount of substance that contains the same number of entities such as molecules, ions, atoms as the number of atoms in $12\text{ g}$ of $\text{C-12}$. The mass of one mole of a substance in grams is called molar mass.

The mass and molar mass of a chemical substance is used to calculate the amount of substance.  The expression to calculate the amount of a substance is as follows:

$\text{Amount }\left(\text{mol}\right)=\left(\text{Mass }\left(\text{g}\right)\right)\left(\frac{\text{1 mol}}{\text{no}\text{. of grams}}\right)$

(b)

Interpretation Introduction

Interpretation:

The amount for $1.36\times {10}^{22}\text{ Cu}$ atoms in moles is to be calculated.

Concept introduction:

One mole is defined as the amount of substance that contains the same number of entities such as molecules, ions, atoms as the number of atoms in $12\text{ g}$ of $\text{C-12}$. This number is called Avogadro’s number. The value of Avogadro’s number is $\text{6}\text{.022}\times {\text{10}}^{23}\left(\text{entitites/mol}\right)$.

Following is the expression to calculate the amount of a chemical substance when the number of atoms is given,

$\text{Amount }\left(\text{mol}\right)=\left(\text{No}\text{. of atoms}\right)\left(\frac{1\text{ mol}}{6.022\times {10}^{23}\text{ atoms}}\right)$

(c)

Interpretation Introduction

Interpretation:

The mass of $8.05\times {10}^{24}\text{ Li}$ atoms in grams is to be calculated.

Concept introduction:

One mole is defined as the amount of substance that contains the same number of entities such as molecules, ions, atoms as the number of atoms in $12\text{ g}$ of $\text{C-12}$. This number is called Avogadro’s number. The value of Avogadro’s number is $\text{6}\text{.022}\times {\text{10}}^{23}\left(\text{entitites/mol}\right)$.

The expression to calculate the mass of a substance when the number of atoms is given is as follows:

$\text{Mass }\left(\text{g}\right)=\left(\text{No}\text{. of atoms}\right)\left(\frac{1\text{ mol}}{6.022\times {10}^{23}\text{ atoms}}\right)\left(\frac{\text{no}\text{. of grams}}{1\text{ mol}}\right)$