Chapter 3, Problem 45P

Interpretation Introduction

(a)

Interpretation:

The total number of valence electrons in of ${\text{NH}}_{\text{3}}$ should be identified.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

8.

Explanation of Solution

Total number valence electrons in ${\text{NH}}_{\text{3}}$ will be sum of valence electrons in n and 3 times the number of valence electrons in hydrogen.

The number of valence electrons in n are 5 and that in hydrogen is 1 thus.

${\text{N}}_{\text{N}{\text{H}}_3}=5+3\left(1\right)=8$

Hence, total number valence electrons in ${\text{NH}}_{\text{3}}$ are 8.

Interpretation Introduction

(b)

Interpretation:

Number of valence electrons in ${\text{C}}_{\text{3}}{\text{H}}_{\text{6}}$ should be identified.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

18.

Explanation of Solution

Total number valence electrons in ${\text{C}}_{\text{3}}{\text{H}}_{\text{6}}$ will be sum of 3 times the valence electrons in C and 6 times the number of valence electrons in hydrogen.

The number of valence electrons in C are 4 and that in hydrogen is 1 thus.

${\text{N}}_{{\text{C}}_{\text{3}}{\text{H}}_{\text{6}}}=3\left(4\right)+6\left(1\right)=18$

Hence, total number valence electrons in ${\text{C}}_{\text{3}}{\text{H}}_{\text{6}}$ are 18.

Interpretation Introduction

(c)

Interpretation:

Number of valence electrons in ${\text{C}}_{\text{2}}{\text{H}}_{\text{4}}{\text{O}}_{\text{2}}$ should be determined.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

24.

Explanation of Solution

Total number valence electrons in ${\text{C}}_{\text{2}}{\text{H}}_{\text{4}}{\text{O}}_{\text{2}}$ will be sum of 2 times the valence electrons in C, 4 times the valence electrons in H and 2 times the number of valence electrons in O.

The number of valence electrons in C are 4, in H is 1and in O are 6 thus.

${\text{N}}_{{\text{C}}_{\text{2}}{\text{H}}_{\text{4}}{\text{O}}_{\text{2}}}=2\left(4\right)+4\left(1\right)+2\left(6\right)=24$

Hence, total number valence electrons in ${\text{C}}_{\text{2}}{\text{H}}_{\text{4}}{\text{O}}_{\text{2}}$ are 24.

Interpretation Introduction

(d)

Interpretation:

Number of valence electrons in ${\text{C}}_{\text{2}}{\text{H}}_{\text{6}}\text{O}$ should be determined.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

20.

Explanation of Solution

Total number valence electrons in ${\text{C}}_{\text{2}}{\text{H}}_{\text{6}}\text{O}$ will be sum of 2 times the valence electrons in C, 6 times the valence electrons in H and the number of valence electrons in O.

The number of valence electrons in C are 4, in H is 1and in O are 6 thus.

${\text{N}}_{{\text{C}}_{\text{2}}{\text{H}}_{\text{6}}\text{O}}=2\left(4\right)+6\left(1\right)+1\left(6\right)=20$

Hence, total number valence electrons in ${\text{C}}_{\text{2}}{\text{H}}_{\text{6}}\text{O}$ are 20.

Interpretation Introduction

(e)

Interpretation:

Number of valence electrons in ${\text{CCl}}_{\text{4}}$ should be determined.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

32.

Explanation of Solution

Total number valence electrons in ${\text{CCl}}_{\text{4}}$ will be sum of the valence electrons in C and 4 times the valence electrons in Cl.

The number of valence electrons in C are 4 and in Cl is 7 thus.

${\text{N}}_{{\text{CCl}}_{\text{4}}}=1\left(4\right)+4\left(7\right)=32$

Hence, total number valence electrons in ${\text{CCl}}_{\text{4}}$ are 32.

Interpretation Introduction

(f)

Interpretation:

Number of valence electrons in ${\text{HNO}}_{\text{2}}$ should be determined.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

18.

Explanation of Solution

Total number valence electrons in ${\text{HNO}}_{\text{2}}$ will be sum of the valence electrons in H, the valence electrons in n and 2 times the number of valence electrons in O.

The number of valence electrons in H is 1, in nitrogen is 5 and in O are 6 thus.

${\text{N}}_{{\text{HNO}}_{\text{2}}}=1\left(1\right)+1\left(5\right)+2\left(6\right)=18$

Hence, total number valence electrons in ${\text{HNO}}_{\text{2}}$ are 18.

Interpretation Introduction

(g)

Interpretation:

Number of valence electrons in ${\text{CCl}}_{\text{2}}{\text{F}}_{\text{2}}$ should be determined.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

32.

Explanation of Solution

Total number valence electrons in ${\text{CCl}}_{\text{2}}{\text{F}}_{\text{2}}$ will be sum of the valence electrons in C, 2 times the valence electrons in Cl and 2 times the number of valence electrons in F.

The number of valence electrons in C is 4, in Cl is 7 and in F is also 7 thus.

${\text{N}}_{{\text{CCl}}_{\text{2}}{\text{F}}_{\text{2}}}=1\left(4\right)+2\left(7\right)+2\left(7\right)=32$

Hence, total number valence electrons in ${\text{CCl}}_{\text{2}}{\text{F}}_{\text{2}}$ are 32.

Interpretation Introduction

(h)

Interpretation:

Number of valence electrons in ${\text{O}}_{\text{2}}$ should be determined.

Concept Introduction:

The number of electrons present in outermost shell of an atom which are available for bonding are known as valence electrons. For a molecule, total number of valence electrons will be sum of valence electrons of each atom present in the molecule.

Answer to Problem 45P

12.

Explanation of Solution

Total number valence electrons in ${\text{O}}_2$ will be 2 times the valence electrons in O.

The number of valence electrons in O are 6, thus.

${\text{N}}_{{\text{O}}_{\text{2}}}=2\left(6\right)=12$

Hence, total number valence electrons in ${\text{O}}_2$ are 12.