11. Bonding & Molecular Structure

Resonance Structures

CHEMISTRY 101 - Drawing Lewis Structures: Resonance, nitrate

Draw Lewis structures for the following: (f) NO3-.

Mothballs are composed of naphthalene, C10H8, a molecule
that consists of two six-membered rings of carbon
fused along an edge, as shown in this incomplete Lewis
structure:
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/5323c6555cc695f8-1661254939258.jpg" alt="" />
(a) Draw all of the resonance structures of naphthalene.
How many are there?

Diazomethane is a highly poisonous, explosive compound because 
it readily evolves N2. Diazomethane has the following 
composition by mass: 28.57% C; 4.80% H; and 66.64% N. The 
molar mass of diazomethane is 42.04 g/mol. Find the molecular 
formula of diazomethane, draw its Lewis structure, and assign 
formal charges to each atom. Why is diazomethane not 
very stable? Explain.

Using only the elements P, Br, and Mg, give formulas for the following.
(b) A molecular compound with polar covalent bonds that obeys the octet rule and has no formal charges

Each compound contains both ionic and covalent bonds. Write 
ionic Lewis structures for each, including the covalent structure 
for the ion in brackets. Write resonance structures if necessary. 
c. KNO3

In the sulphate ion, SO42-, the sulphur atom is the central
atom with the other 4 oxygen atoms attached to it. 
(d) How many electrons are in the p system of the ion?

The cyanate ion (OCN- ) and the fulminate ion (CNO- ) share
the same three atoms but have vastly different properties. The
cyanate ion is stable, while the fulminate ion is unstable and
forms explosive compounds. The resonance structures of the
cyanate ion are explored in Example 9.8. Draw Lewis structures
for the fulminate ion—including possible resonance forms—
and use formal charge to explain why the fulminate ion is less
stable (and therefore more reactive) than the cyanate ion.

Sodium azide is a shock-sensitive compound that releases
N2 upon physical impact. The compound is used in automobile
airbags. The azide ion is N3-. (a) Draw the Lewis
structure of the azide ion that minimizes formal charge
(it does not form a triangle). Is it linear or bent? 

Draw the Lewis structure of the azide ion that minimizes formal charge
(it does not form a triangle).

Draw as many resonance structures as you can for the following nitrogen-containing compounds. Not all will obey the octet rule. Use curved arrows to depict the conversion of one structure into another.
(d) N2O31ONNO22

Resonance Structures, Basic Introduction - How To Draw The Resonance Hybrid, Chemistry

Sulfur tetrafluoride 1SF42 reacts slowly with O2 to form sulfur
tetrafluoride monoxide 1OSF42 according to the following
unbalanced reaction:
SF41g2 + O21g2¡OSF41g2
The O atom and the four F atoms in OSF4 are bonded to a
central S atom. (b) Write a Lewis
structure of OSF4 in which the formal charges of all atoms
are zero.

The following three Lewis structures can be drawn for N2O:
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/69b8b7a3945a6fa4-1664471049449.jpg" alt="" />
(b) The N¬N bond length in N2O is 112 pm, slightly longer than a typical N‚N bond; and the N¬O bond length is 119 pm, slightly shorter
than a typical N“O bond (see Table 8.4). Based on these
data, which resonance structure best represents N2O?

Assign formal charges to the atoms in the following structures. Which of the two do you think is the more important contributor to the resonance hybrid?
(a) <img src="" alt="" />
(b) <img src="" alt="" />

Resonance Structures of NO3(-1), nitrate ion

The hypochlorite ion, ClO-, is the active ingredient in 
bleach. The perchlorate ion, ClO4-, is a main component 
of rocket propellants. Draw Lewis structures for both ions. 
(b) What is the formal charge of Cl in the perchlorate ion, assuming 
the Cl—O bonds are all single bonds?

How important is the resonance structure shown here to the
overall structure of carbon dioxide? Explain.
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/793181e7764380c0-1662574010138.jpg" alt="" />

Draw three resonance structures for sulfur tetroxide, SO4, whose connections are shown below. (This is a neutral mol-ecule; it is not a sulfate ion.) Assign formal charges to the atoms in each structure.

Carbon ring structures are common in organic chemistry. Draw 
a Lewis structure for each carbon ring structure, including any 
necessary resonance structures. 
d. C6H6

Which of the following pairs represent resonance structures? (LO 7.13)
(a) <img src="" alt="" />
(b) <img src="" alt="" />
(c) <img src="" alt="" />

Draw the Lewis structure (including resonance structures) for
methyl azide (CH3N3). For each resonance structure, assign
formal charges to all atoms that have formal charge.

Resonance Structures Example 1

Four different structures (a), (b), (c), and (d) can be drawn for compounds named dibromobenzene, but only three different compounds actually exist. Explain.
(a) <img src="https://lightcat-files.s3.amazonaws.com/problem_images/7de2e4b48570a3be-1670449750419.jpg" alt="" />
(b) <img src="https://lightcat-files.s3.amazonaws.com/problem_images/c4ef7a99f6c8b2be-1670449746616.jpg" alt="" />
(c) <img src="https://lightcat-files.s3.amazonaws.com/problem_images/4737d462951921a8-1670449741830.jpg" alt="" />
(d) <img src="https://lightcat-files.s3.amazonaws.com/problem_images/40bf4e227a1b6c7d-1670449712180.jpg" alt="" />

Use formal charge to select which resonance structure makes the largest contribution to the resonance hybrid. (LO 7.16)
(a) Structure I 
(b) Structure II 
(c) Structure III 
(d) All structures are equivalent and make the same contri-bution to the resonance hybrid.

(I) <img src="" alt="" />
(II) <img src="" alt="" />
(III) <img src="" alt="" />

In the sulphate ion, SO42-, the sulphur atom is the central 
atom with the other 4 oxygen atoms attached to it. 
(c) Are there multiple equivalent resonance structures for the ion?

Resonance Structures Example 2

The structure of borazine, B3N3H6, is a six-membered ring 
of alternating B and N atoms. There is one H atom bonded 
to each B and to each N atom. The molecule is planar. 
(a) Write a Lewis structure for borazine in which the formal 
charge on every atom is zero.

Using only the elements Ca, Cl, and Si, give formulas for the following.
(b) A molecular compound with polar covalent bonds that obeys the octet rule and has no formal charges

1,2-dihydroxybenzene is obtained when two of the adjacent
hydrogen atoms in benzene are replaced with an OH group.
A skeleton of the molecule is shown here. (b) Are there any resonance structures for the molecule? If so, sketch them. 
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/100660e4f2630eea-1661265098358.jpg" alt="" />

Determine the average charge of the oxygen atoms within the chlorite ion, ClO2–.

Resonance & Bond Order

Write a Lewis structure that obeys the octet rule for each molecule
or ion. Include resonance structures if necessary and assign
formal charges to each atom.
a. SeO2

 This is an ionic compound and has only one valid Lewis structure. 

 There is only one valid Lewis structure for the ammonium ion. 

 There is only one valid Lewis structure for carbon disulfide. 

 Correct, there are two valid Lewis structures for the nitrite ion. 

 Draw the Lewis structure for each and determine if more than one valid Lewis structure is possible. 

 Which of the following substances exhibits resonance? 

(a) Describe the molecule xenon trioxide, XeO3, using 
four possible Lewis structures, one each with zero, one, 
two, or three Xe¬O double bonds. (b) Do any of these 
resonance structures satisfy the octet rule for every atom 
in the molecule? (c) Do any of the four Lewis structures 
have multiple resonance structures? If so, how many resonance 
structures do you find? (d) Which of the Lewis 
structures in part (a) yields the most favorable formal 
charges for the molecule?

Drawing Lewis Structures: Resonance Structures - Chemistry Tutorial

Draw as many resonance structures as you can for the following nitrogen-containing compounds. Not all will obey the octet rule. Use curved arrows to depict the conversion of one structure into another.
(b) NO<img src="https://lightcat-files.s3.amazonaws.com/problem_images/328e46700545fce9-1670386717125.jpg" alt="" />

The structure for the DNA base cytosine is shown. 
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/540034dfcf08855c-1670524634010.jpg" alt="" />
Which of the following is not a resonance structure of cytosine? (LO 7.13)
(a) <img src="" alt="" />
(b) <img src="" alt="" />
(c) <img src="" alt="" />
(d) <img src="" alt="" />

There are many Lewis structures you could draw for sulfuric
acid, H2SO4 (each H is bonded to an O). (b) What Lewis structure(s) would you draw to minimize formal charge?

The azide ion, N3- , is a symmetrical ion, all of whose contributing
resonance structures have formal charges. Draw three important
contributing structures for this ion.

Draw all the resonance structures for the following ionic compound:RbIO2

Draw the resonance structure indicated by the curved arrows. Assign formal charges, and evaluate which of the two structures is a larger contributor to the resonance hybrid.
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/52e2b65920afb9f7-1670446748357.jpg" alt="" />

Mothballs are composed of naphthalene, C10H8, a molecule
that consists of two six-membered rings of carbon
fused along an edge, as shown in this incomplete Lewis
structure:
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/4a885d3232a688bb-1661347518929.jpg" alt="" />
(b) Do you expect the C¬C bond lengths in the molecule to be similar to those of C¬C single bonds, C“C double bonds, or intermediate between
C¬C single and C“C double bonds?

Resonance Structures of N2O (dinitrogen monoxide, nitrous oxide)

Draw all possible resonance structures for the chlorate ion, ClO3–?

Some chemists believe that satisfaction of the octet rule 
should be the top criterion for choosing the dominant Lewis 
structure of a molecule or ion. Other chemists believe that 
achieving the best formal charges should be the top criterion. 
Consider the dihydrogen phosphate ion, H2PO4-, in which the H atoms are bonded to O atoms. 
(b) What is the predicted dominant 
Lewis structure if achieving the best formal charges is the top 
criterion?

For each of the following molecules or ions of sulfur and
oxygen, write a single Lewis structure that obeys the octet
rule, and calculate the oxidation numbers and formal
charges on all the atoms: (c) SO32-
Write a single Lewis structure that obeys the octet rule for SO3 2 - and assign the formal charges on all the atoms.

Which of the following pairs of structures represent resonance forms, and which do not?
(a)

The dichromate ion, Cr2O72-, has neither Cr¬Cr nor 
O¬O bonds. 
(a) Taking both 4s and 3d electrons into account, draw an 
electron-dot structure that minimizes the formal charges 
on the atoms.

Draw the Lewis structure (including resonance structures) for
the acetate ion (CH3COO- ). For each resonance structure,
assign formal charges to all atoms that have formal charge.

 a double bond between carbon and nitrogen. 

 Correct, with a double bond between carbon and sulfur also. 

 one lone pair of electrons on nitrogen. 

 There a two lone pairs of electrons on nitrogen. 

 a triple bond between carbon and sulfur. 

 There is a double between carbon and sulfur. 

 The negative formal charge is on the more electronegative nitrogen. 

 a single bond between carbon and nitrogen. 

 There is a double bond carbon and nitrogen. 

Draw the Lewis structure for NCS&#8722;and calculate formal charges.

The Lewis structure that is likely to contribute the most to the overall structure of NCS&#8722; should have:

Each compound contains both ionic and covalent bonds. Write
ionic Lewis structures for each, including the covalent structure
for the ion in brackets. Write resonance structures if necessary.
a. BaCO3

Resonance | General Chemistry II | 1.6

A major challenge in implementing the “hydrogen economy” 
is finding a safe, lightweight, and compact way of storing 
hydrogen for use as a fuel. The hydrides of light metals 
are attractive for hydrogen storage because they can store a 
high weight percentage of hydrogen in a small volume. For 
example, NaAlH4 can release 5.6% of its mass as H2 upon 
decomposing to NaH1s2, Al1s2, and H21g2. NaAlH4 possesses 
both covalent bonds, which hold polyatomic anions 
together, and ionic bonds. (d) What is the formal charge on hydrogen 
in the polyatomic ion?

Average Charge is the charge of an element from overall charges of ALL its resonance structures.&nbsp;

Benzene has the following structural formula.
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/8b52498ba4b24ca8-1670447930529.jpg" alt="" />
(b) Which statement best describes the carbon–carbon bonds in benzene?
(i) Three carbon–carbon bonds are longer and weaker than the other three carbon–carbon bonds.
(ii) All six carbon–carbon bonds are identical, and their length and strength are between a double and single bond.
(iii) The length of carbon–carbon double bond switches back and forth between the length of a double and a single bond.

Write a Lewis structure that obeys the octet rule for each ion.
Include resonance structures if necessary and assign formal
charges to each atom.
a. ClO3-
b. ClO4-
c. NO3-
d. NH4+

Resonance Hybrid is made up of all the major resonance structures.&nbsp;

Which of the following phosphate, PO43- Lewis structures is the best, most valid resonance structure?<img src="https://static.studychannel.pearsonprd.tech/courses/general-chemistry/thumbnails/images/edd7c3df"class="fr-fic fr-dii">

Consider the formate ion, HCO2-, which is the anion
formed when formic acid loses an H+ ion. The H and the two
O atoms are bonded to the central C atom. (b) Are resonance structures needed to describe the structure?

The hypochlorite ion, ClO-, acts as a weak base. (b) When ClO- acts as a base, which atom, Cl or O, acts as the proton acceptor? (c) Can you use formal charges to rationalize your answer to part (b)?

In the cyanate ion, OCN-, carbon is the central atom.
(b) Which resonance structure makes the greatest contribution
to the resonance hybrid? Which makes the least
contribution? Explain.

Determine which of the following drawings would be the best structure for the N2O molecule.<img src="https://static.studychannel.pearsonprd.tech/courses/general-chemistry/thumbnails/images/fbabe4b1"class="fr-fic fr-dii">&nbsp;a) a&nbsp;b) bc) cd) All are equally stable

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1. Intro to General Chemistry

2. Atoms & Elements

3. Chemical Reactions

4. BONUS: Lab Techniques and Procedures

5. BONUS: Mathematical Operations and Functions

6. Chemical Quantities & Aqueous Reactions

7. Gases

8. Thermochemistry

9. Quantum Mechanics

10. Periodic Properties of the Elements

12. Molecular Shapes & Valence Bond Theory

13. Liquids, Solids & Intermolecular Forces

14. Solutions

15. Chemical Kinetics

16. Chemical Equilibrium

17. Acid and Base Equilibrium

18. Aqueous Equilibrium

19. Chemical Thermodynamics

20. Electrochemistry

21. Nuclear Chemistry

22. Organic Chemistry

23. Chemistry of the Nonmetals

24. Transition Metals and Coordination Compounds

[BOOK CHEM] Clutch Version

Lewis Dot Structures: Neutral Compounds

Lewis Dot Structures or Electron Dot Structures&nbsp;are diagrams that show how elements in a molecule use their valence electrons to form bonds.&nbsp;

Average Bond Order

Average Bond Order represents the average number of chemical bonds between a pair of bond elements.

Lewis Dot Structures: Ions

Lewis Dot Structures of Ions involves losing or gaining valence electrons to draw the most likely structure.&nbsp;

Octet Rule

The&nbsp;Octet Rule states that main-group elements will generally form enough bonds to obtain 8 electrons in their valence shell.&nbsp;

Lewis Dot Symbols

Lewis Dot Symbols represent the outer shell electrons of an element.&nbsp;

Lewis Dot Structures: Sigma & Pi Bonds

Sigma Bonds directly connect element together, while Pi Bonds provide insulation and protection for those bonds.&nbsp;

Lewis Dot Structures: Exceptions

Lewis Dot Structure Exceptions&nbsp;happen when the central element violates the Octet Rule.

Born Haber Cycle

In the Born-Haber Cycle, ionic solids are created through the ionization and eventual combination of elements.&nbsp;

Coulomb's Law

Coulomb's Law is used to determine the forces experienced by charged particles.&nbsp;

Chemical Bonds

A chemical bond is the connection&nbsp;of different elements through the sharing, transferring or pooling of electrons.&nbsp;

Resonance Structures are used to represent the different possible bonding arrangements of a molecule.

Lewis Dot Structures: Acids

Drawing the Lewis Dot Structure of Acids&nbsp;involves first drawing the polyatomic anion and then attaching the H+ ion.&nbsp;

Formal Charge

Formal Charge is the charge given to an element within a molecule when assuming equal sharing of electrons between bonded elements.&nbsp;

Bond Energy

Bond Energy is the amount of energy stored within a chemical bond.

Lattice Energy

Lattice Energy&nbsp;is the estimate for the strength of ionic bonds.&nbsp;

Dipole Moment

Dipole arrows are used anytime a molecule possesses a dipole moment, which happens when a molecule is polar.&nbsp;