Chapter 11, Problem 11.2P

(a)

Interpretation Introduction

Interpretation:

The mass of $\text{3}\text{.00 moles}$ of $\text{Hg}\left(l\right)$ has to be determined.

Concept Introduction:

Mole is the S.I. unit. The number of moles is calculated as ratio of mass of compound to that of molar mass of the compound.

Molar mass is sum of total mass in grams of all atoms that make up mole of particular molecule that is mass of 1 mole of compound. Its S.I unit is $\text{g/mol}$.

The expression for number of moles, mass and molar mass of compound is as follows:

  $\text{Number of moles}=\frac{\text{mass of the compound}}{\text{molar mass of the compound}}$

(b)

Interpretation Introduction

Interpretation:

The mass of $1.872\times {10}^{24}\text{ molecules}$ of $\text{Fe}{\left(\text{OH}\right)}_{\text{3}}$ has to be determined.

Concept Introduction:

One mole of any substance has $6.022\times {10}^{23}$ formula units and this number is called Avogadro’s number.

The expression is as follows:

    $1\text{ mole}=6.022\times {10}^{23}\text{ molecules}$

(c)

Interpretation Introduction

Interpretation:

The mass in $\text{1 mole}$ of ${}^{18}\text{O}$ atoms has to be determined.

Concept Introduction:

Refer to part (a).

(d)

Interpretation Introduction

Interpretation:

The mass of $\text{2}\text{.00 moles}$ of ${\text{N}}_2$ has to be determined.

Concept Introduction:

Refer to part (a).