11. Bonding & Molecular Structure

Lewis Dot Structures: Sigma & Pi Bonds

9.4 Sigma and Pi Bonds | General Chemistry

Some mothballs used when storing clothes are made of naphthalene (C10H8), which has the following incomplete structure.
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/747cc07087442ab9-1670360220433.jpg" alt="" />
(a) Add double bonds where needed to draw a complete electron-dot structure.

The partial Lewis structure that follows is for a hydrocarbon 
molecule. In the full Lewis structure, each carbon atom 
satisfies the octet rule, and there are no unshared electron 
pairs in the molecule. The carbon—carbon bonds 
are labeled 1, 2, and 3. (c) Which 
carbon—carbon bond is the strongest one? 
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/590426dd801d3ddc-1661188945104.jpg" alt="" />

Lewis Dot Structures

Butadiene, C4H6, is a planar molecule that has the following 
carbon–carbon bond lengths: 
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/29f88db06908f6ee-1661252224372.jpg" alt="" /> 
(c) The middle C¬C bond length in butadiene (148 pm) is 
a little shorter than the average C¬C single bond length 
(154 pm). Does this imply that the middle C¬C bond in 
butadiene is weaker or stronger than the average C¬C 
single bond?

Propose structures for molecules that meet the following 
descriptions. 
(b) Contains an N atom that has one p bond and two s bonds

Compare the O—O bond length in O2 versus H2O2. Which 
bond is shorter? Why?

What’s the difference between sigma and pi bonds

Order these compounds in order of increasing carbon–carbon
bond strength: HCCH, H2CCH2, H3CCH3.

Lewis Dot Structures: Sigma & Pi Bonds Example 1

The following ball-and-stick molecular model is a representation
of acetaminophen, the active ingredient in such over-thecounter
headache remedies as Tylenol. 1Red = O, gray = C,
blue = N, ivory = H.2
(b) Indicate the positions of the multiple bonds in
acetaminophen.
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/b677cb75d056022d-1670523351514.jpg" alt="" />

Which molecule has the shortest carbon–oxygen bond? (LO 7.3, 7.9) 
(a) CH3OH
(b) CO 
(c) CO2 
(d) HCOOH

Order these compounds in order of decreasing carbon–carbon bond
length: HCCH, H2CCH2, H3CCH3.

Draw the total number of sigma and pi bonds of the sulfur trioxide molecule, SO3.

In the hydrocarbon 
 
(b) How many s bonds are there in the molecule?

(c) Which is generally stronger, a s bond or a p bond? Explain.

Acrylonitrile 1C3H3N2 is a molecule that is polymerized to 
make carpets and fabrics. The connections between atoms 
are shown. 
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/5c56685763b8be94-1670432336200.jpg" alt="" /> 
(d) Identify the shortest bond in the molecule.

Consider the molecule C4H5N, which has the connectivity
shown below. (a) After the Lewis structure for the molecule
is completed, how many s and how many p bonds are
there in this molecule?
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/15c270e62b80fafe-1661187920471.jpg" alt="" />

(b) Imagine that you could hold two atoms that are bonded 
together, twist them, and not change the bond length. Would 
it be easier to twist (rotate) around a single s bond or around a 
double 1s plus p2 bond, or would they be the same?<img src="https://lightcat-files.s3.amazonaws.com/problem_images/cff843961da00898-1661190579341.jpg" alt="" />

The structure of acetylsalicylic acid (aspirin) is shown here. How many sigma bonds?
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/9ea0d51da97cac6e-1660047545749.jpg" alt="" />

Sigma and Pi Bonds

Drawing Lewis Structures with Multiple Bonds

Consider the Lewis structure for acetic acid, which is known
as vinegar:
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/9f6ad3f9cfbd5be8-1661187673380.jpg" alt="" />
(c) What is the total number of s bonds in the
entire molecule, and what is the total number of p bonds?

How many sigma bonds does the following molecule contain?<img src="https://static.studychannel-prd.pearsonprd.tech/courses/general-chemistry/thumbnails/images/a1cd73ca"class="fr-fic fr-dii">

The drawing below shows the overlap of two hybrid orbitals 
to form a bond in a hydrocarbon. (a) Which of the following 
types of bonds is being formed: (i) C¬C s, (ii) C¬C p, 
or (iii) C¬H s?
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/cc55fbb23e2c21ed-1661263958212.jpg" alt="" />

Which of the two compounds, H2NNH2 and HNNH, has the strongest nitrogen-nitrogen bond, and which has the shorter nitrogen-nitrogen bond.

Bupropion, marketed as Wellbutrin, is a heavily prescribed 
medication used in the treatment of depression. Complete 
the following electron-dot structure for Bupropion by adding 
lone pairs of electrons.
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/b9773a0f85537791-1670374020145.jpg" alt="" />
(a) How many s and how many p bonds are in the molecule?

Based on Lewis structures, predict the ordering, from shortest
to longest, of N¬O bond lengths in NO+, NO2-, and NO3-.

Which has greater bond strength between the carbon–carbon bond.C2Cl2&nbsp; vs. &nbsp;C2Cl6

How many pi bonds does the following molecule contain?&nbsp;<img data-fr-image-pasted="true"src="https://static.studychannel-prd.pearsonprd.tech/courses/general-chemistry/thumbnails/images/e571517c"width="227"height="195"class="fr-fic fr-dii">

The following diagram shows the potential energy of two atoms as a function of internuclear distance. Which bond is the strongest? Which bond is the longest?
<img src="https://lightcat-files.s3.amazonaws.com/problem_images/904a8aa0da2a634a-1670434262996.jpg" alt="" />

Sigma and Pi Bonds Explained, Basic Introduction, Chemistry

Estimate the P¬Cl bond length from the data in Figure 7.7
and compare your value to the experimental P¬Cl bond
length in phosphorus tetrachloride PCl3, 204 pm.<img src="https://lightcat-files.s3.amazonaws.com/problem_images/5ed9d89089913c60-1664467761451.jpg" alt="" />

(c) Do you expect the O¬O bond in H2O2 to be longer or 
shorter than the O¬O bond in O2? Explain.

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21. Nuclear Chemistry

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[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;

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

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;