Chapter 9, Problem 30E

For each of the following molecules or ions that contain sulfur, write the Lewis structure(s), predict the molecular structure (including bond angles), and give the expected hybrid orbitals for sulfur.

a. SO₂

b. SO₃

c.

d.

e. SO₃²⁻

f. SO₄²⁻

g. SF₂

h. SF₄

i. SF₆

j. F₃S—SF

k. SF₅+

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SO}}_{\text{2}}$.

Explanation of Solution

Explanation

There are six valence electrons on each sulfur and oxygen atom. Two oxygen atoms are bonded to sulfur atom. Therefore, the total valence electrons are $6+6\times 2=18$. Between each sulfur and oxygen, there is a sigma and pi bond. There is a lone pair of electron on sulfur which pushes the oxygen atom down.

Therefore the geometry is bent. The bond angle is less than ${\text{120}}^{\text{ο}}$. The sulfur utilizes one $s$ and two $p$ orbitals to give hybridization $s{p}^2$.

The Lewis structure of ${\text{SO}}_{\text{2}}$ is,

Figure 1

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SO}}_3$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and each oxygen atom. Two oxygen atoms are attached to sulfur, therefore, the total number of valence electrons is $6+6\times 3=24$. There are three bond pairs of electrons surrounding the sulfur atom. The oxygen that is double bonded with sulfur has two lone pair and the other two oxygen atoms have three lone pairs of electrons.

The molecule has trigonal planar geometry with bond angle ${120}^{\text{ο}}$. The sulfur atom is doubly bonded to each oxygen, which means one $s$ and two $p$ orbitals are hybridized hence the hybridization of sulfur is $s{p}^2$. The Lewis structure of ${\text{SO}}_3$ is,

Figure 2

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{S}}_2{\text{O}}_3{}^{2-}$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and each oxygen atom. Three oxygen atoms and one sulfur atom is attached to central sulfur atom and charge on the molecule is $-2$, therefore, the total number of valence electrons is $2\times 6+6\times 3+2=32$. The sulfur is bonded to one sulfur atom and one of the oxygen atoms by pi bond and other two oxygen atoms are bonded by sigma bond.

By bonding in this way, they complete their octet. The molecular structure is tetrahedral with bond angle approximately equal to $\text{109}{\text{.5}}^{\text{ο}}$. The hybridization of central sulfur atom is $s{p}^3$. The Lewis structure of ${\text{S}}_2{\text{O}}_3{}^{2-}$ is,

Figure 3

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{S}}_2{\text{O}}_8{}^{2-}$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and each oxygen atom. There are eight oxygen atoms and two sulfur atoms are present in the molecule and charge on the molecule is $-2$, therefore, the total number of valence electrons is $2\times 6+6\times 8+2=62$. Each sulfur is bonded to four oxygen atoms, two oxygen atoms are double bonded while two are single bonded.

The two oxygen atoms in the centre are bonded by single bond. By bonding in this way, they complete their octet. The molecular structure is tetrahedral with bond angle approximately equal to $\text{109}{\text{.5}}^{\text{ο}}$. The hybridization of both sulfur atom is $s{p}^3$. The Lewis structure of ${\text{S}}_2{\text{O}}_8{}^{2-}$ is,

Figure 4

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SO}}_3{}^{2-}$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and each oxygen atom. Three oxygen atoms and one sulfur atom present in the molecule and charge on the molecule is $-2$, therefore, the total number of valence electrons is $6+6\times 3+2=26$. The sulfur is bonded to three oxygen atoms.

One oxygen atom is single bonded with sulfur and one is joined by pi bond. By bonding in this way, they complete their octet. The molecular structure is trigonal pyramidal with bond angle approximately equal to $\text{109}{\text{.5}}^{\text{ο}}$. The hybridization of sulfur atom is $s{p}^3$. The Lewis structure of ${\text{SO}}_3{}^{2-}$ is,

Figure 5

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SO}}_4{}^{2-}$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and each oxygen atom. Four oxygen atoms and one sulfur atom is present in the molecule and charge on the molecule is $-2$, therefore, the total number of valence electrons is $6+6\times 4+2=32$. The sulfur is bonded to four oxygen atoms.

Two oxygen atoms are single bonded with sulfur and two joined by pi bond. By bonding in this way, they complete their octet. The molecular structure is tetrahedral with bond angle approximately equal to $\text{109}{\text{.5}}^{\text{ο}}$. The sulfur has no lone pairs of electrons and is attached four oxygen atoms, thus the hybridization of sulfur atom is $s{p}^3$. The Lewis structure of ${\text{SO}}_4{}^{2-}$ is,

Figure 6

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SF}}_2$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and seven valence electrons on each fluorine atom. Two fluorine atoms and one sulfur atom is present in the molecule, therefore, the total number of valence electrons is $6+7\times 2=20$.

The sulfur is bonded to two fluorine atoms by sigma bond. By bonding in this way, they complete their octet. The molecular structure is bent due to presence of lone pairs of electrons on sulfur. The bond angle is less than $\text{109}{\text{.5}}^{\text{ο}}$ and there are four hybrid orbitals present, thus the hybridization of sulfur atom is $s{p}^3$. The Lewis structure of ${\text{SF}}_2$ is,

Figure 7

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SF}}_4$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and seven valence electrons on each fluorine atom. Four fluorine atoms and one sulfur atom is present in the molecule, therefore, the total number of valence electrons is $6+7\times 4=34$. The sulfur is bonded to four fluorine atoms by sigma bond. By bonding in this way, they complete their octet. One lone pair of electron is present on sulfur.

The molecular structure is see-saw due to presence of lone pair of electrons on sulfur. The equatorial bond angles are ${\text{120}}^{\text{ο}}$ and the axial bond angle is ${\text{90}}^{\text{ο}}$ and four hybrid orbitals are required for the accommodation of four bonding electron and one lone pair on sulfur, thus the hybridization of sulfur atom is $s{p}^{3}d$. The Lewis structure of ${\text{SF}}_4$ is,

Figure 8

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SF}}_6$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and seven valence electrons on each fluorine atom. Six fluorine atoms and one sulfur atom is present in the molecule, therefore, the total number of valence electrons is $6+7\times 6=48$. The sulfur is bonded to six fluorine atoms by sigma bond. By bonding in this way, they complete their octet. No lone pair of electron is present on sulfur.

The molecular structure is octahedral with bond angle ${\text{90}}^{\text{ο}}$ and each electron from $3s$ and $3p$ orbitals are promoted to $3d$ orbitals for the formation of six sigma bonds with fluorine atoms, thus the hybridization of sulfur atom is $s{p}^3{d}^2$. The Lewis structure of ${\text{SF}}_6$ is,

Figure 9

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{F}}_{\text{3}}\text{S}-\text{SF}$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and seven valence electrons on each fluorine atom. Four fluorine atoms and two sulfur atoms are present in the molecule, therefore, the total number of valence electrons is $2\times 6+7\times 4=40$. Two sulfur atoms are joined by single bond. Three fluorine atoms are attached to one sulfur and one fluorine atom is attached to another sulfur atom. By bonding in this way, they complete their octet. One lone pair of electron is present on one sulfur and two lone pair of electrons are present on another sulfur.

The molecular structure is see-saw due to presence of lone pair of electrons on sulfur. The equatorial bond angles are ${\text{120}}^{\text{ο}}$ and the axial bond angle is ${\text{90}}^{\text{ο}}$. Four hybrid orbitals are required for the accommodation of four bonding electron and one lone pair on sulfur, thus the hybridization of sulfur atom bonded to three fluorine atoms is $s{p}^{3}d$. The hybridization of sulfur bonded with only one fluorine is $s{p}^3$.

The Lewis structure of ${\text{F}}_{\text{3}}\text{S}-\text{SF}$ is,

Figure 10

Interpretation Introduction

Interpretation: The Lewis dot structure, molecular geometry, bond angles of the given molecules and expected hybrid orbitals for sulfur is to be stated.

Concept introduction: When the atomic orbitals overlap with each other in the region where density of electrons is high, then molecular orbitals are formed. Overlap of the atomic orbitals determines the efficiency of the interaction between the atomic orbitals.

Energy of bonding molecular orbitals is less than the nonbonding molecular orbitals.

To determine: The Lewis dot structure, molecular geometry, bond angles and expected hybrid orbitals for sulfur in ${\text{SF}}_5{}^{+}$.

Explanation of Solution

Explanation

There are six valence electrons on sulfur and seven valence electrons on each fluorine atom. Five fluorine atoms and one sulfur atom is present in the molecule and charge on the molecule is $+1$, therefore, the total number of valence electrons is $6+7\times 5-1=40$. The sulfur is bonded to five fluorine atoms by sigma bond. By bonding in this way, they complete their octet.

The molecular structure is trigonal bipyramidal with equatorial bond angles ${\text{120}}^{\text{ο}}$ and the axial bond angle ${\text{90}}^{\text{ο}}$. The sulfur has no lone pairs of electrons and is attached to five fluorine atoms, thus the hybridization of sulfur atom is $s{p}^{3}d$.

The Lewis structure of ${\text{SF}}_5{}^{+}$ is,

Figure 11