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Unit 1 Packet: Background, Lewis Structures, Resonance,
Formal Charge, VSEPR, Hybridization,
Isomerism, Acids and Bases
Honors Organic Chemistry
2
Key Terms For Unit 1 General
Organic Chemistry
Orbital
Orbital Notation
Isomerism
Structural Isomerism
Geometric Isomerism
Bonding
Anion
Aufbau Principle
Bond Angle
Bond Length
Cation
Covalent Bond
Double Bond
Electronegativity
Formal Charge
Full Octet
Hindered Rotation
Hund’s Rule
Hybridization
Ionic Bond
Line Angle
Non-polar covalent bond
Octet Rule
Pauli exclusion Principle
Polar covalent bond
Pi bond (π)
Resonance hybrid
Sigma bond (σ)
sp hybrid orbital
sp2 hybrid orbital
sp3 hybrid orbital
Tetrahedron
Trigonal Planar
Valence Electrons
Valence Shell
Valence Shell Electron-
Pair Repulsion
Nomenclature
Alcohol
Aldehyde
Carbonyl group
Carboxyl group
Carboxylic Acid
Ether
Functional Group
Ketone
Acids and Bases
Ka
pKa
pH
Strong Acid
Weak Acid
Conjugate Acid/Base Pair
Bronsted-Lowry Acid
Bronsted-Lowry Base
Lewis Acid
Lewis Base
Nucleophile
Electrophile
Honors Organic Chemistry
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What is Organic Chemistry?
Organic Chemistry:
What makes carbon so special?
What other elements are commonly involved?
Important Dicsovery: Friedrich Wohler (1828) – Accidental synthesis of Urea ( ____________ )
from ammonium cyanate (___________ ).
Atomic Structure Review
Any atom is made up of three subatomic particles: __________, __________ and __________.
Two atoms of the same element with different numbers of ___________ are called __________.
An atom of an element with different numbers of __________ and __________ are called _____.
Anions are _______________ charged ions. Ex: ________
Cations are _______________ charged ions. Ex: ________
In Chemistry, the subatomic particle that we are most concerned with is the ___________, and
particularly, the ____________ in the outermost, or _____________ shell. These are the
particles that allow different atoms to ________ with one another.
Electrons
Electrons are located in…
Principle Energy Levels:
Sublevels:
Orbitals:
Electrons can be represented visually using
orbital notation
Honors Organic Chemistry
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Ground State Orbital Notation
Orbital Notation is a visual method to represent the ________ ________, ___________,
_________ and ____ of each electron in an atom or ion. The ground state of an atom represents
its lowest energy, preferred configuration.
The placing of electrons into an orbital notation is governed by three rules:
Aufbau Principle:
Hund’s Rule:
Pauli Exclusion Principle:
To practice using orbital notation, consider the ground state configurations of carbon and
bromine:
Carbon, Z = 6 Bromine, Z = 35
Lewis Dot Diagrams
Since we are primarily concerned with the __________ _________ in an atom, a scientist named
G. N. Lewis devised another method of representing an atom that is commonly used called a
Lewis Dot Diagram. Let’s consider how these are drawn for several elements.
H C P Xe I
**We can piece these diagrams together to make
Lewis structures for molecules. Ex: H2O, water**
Honors Organic Chemistry
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Lewis Structures
History:
Purpose:
Process:
CH4 COCl2 NO3-
1. Predict the Arrangement of
the atoms:
2. Count up the valence
electrons
3. Connect the surrounding
atoms to the central atom with
single bond (one shared pair)
4. Determine how many
electron pairs you have left
5. Place lone pairs around
terminal atoms to satisfy octet
(stick any leftovers on central
atom)
6. If the central atom has not
achieved an octet, form
multiple bonds to do so
Honors Organic Chemistry
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Lewis Structures – Additional Practice
CO
NH3
CH2O
CO32-
SOCl2
C2H4
Resonance Structures
Often, it is possible to draw more that one legal Lewis structure for a molecule.
e.g. NO3-
Each of these structures fulfills the requirements of a __________ ____________, therefore, they
are each valid resonance structures. No single one of these resonance structures gives a
_________ picture of what the ion looks like. A resonance structure is a Lewis structure that
contributes to the overall resonance _________ of a molecule or polyatomic ion.
Another example of resonance, the sulfate ion (SO42-
), involves a concept called expanded octet.
e.g. SO42-
Honors Organic Chemistry
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Resonance Hybrids – What does a molecule really look like?
Similar to restaurant Diet Coke mixtures, not all of the resonance structures that can be drawn for
a sulfate ion are created equal. How do we decide which ones contribute most to the actual
picture of what a molecule looks like? To do this, we have to minimize the formal charge of
each atom.
e. g. CO2
By minimizing the formal charge on each atom, we can isolate the resonance structure that best
represents what a molecule or ion looks like.
Try some others:
C2O42-
SO32-
Evidence for Resonance – Benzene
General Guidelines for Resonance Structures
1. Try to draw structures that are as low in energy as possible
2. The best structures tend to have the maximum number of bonds and the most octets
3. When structures are equivalent in terms of bonds and octets, minimize formal charge
to find the more stable structure
4. All structures must be valid. Only electrons may be moved to change between
structures, bonding sequence of atoms must remain the same.
5. Use curved arrows to show the movement of electrons. Only move lone pairs and
multiple bonds.
6. Separate resonance structures by a double headed arrow.
7. Resonance stabilization is very important when it delocalizes or spreads a charge over
two or more atoms
8. Negative formal charges are more stable on atoms with higher electronegativities.
A commonly cited example of evidence for the
resonance theory is the molecule benzene (C6H6). In a
Lewis diagram of benzene, the carbons can be
connected by either a single or double covalent bond.
The known length of a C=C double bond is 133 pm, the
known length of a C-C single bond is 154 pm, but the
bond length of every carbon-carbon bond in benzene is
139 pm, a value in between that of a single and double.
Honors Organic Chemistry
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Worksheet – Resonance and Formal Charge
1. For each of the following compounds, draw the important resonance structures.
Indicate which structures are major and minor contributors or whether they have the
same energy
.. (-)
H :O: H
| | .. (-) |
a. H – C = N – O:
(+) ..
:O:
|| ..
b. H – C – NH2
.. :O – H
| c. H – C – H
(+)
H
| .. .. d. H – C – N = N:
(+) (-)
e. H – C – C ≡ N:
..
(-)
:O:
.. || .. f. H2C – C – O – CH3
..
(-)
:O: :O:
|| .. || g. H – C – C – C – H
| H
(-)
2. Draw the important resonance structures for the following ions
(+) (-)
a. H2C = CH – CH2 b. H2C = CH – CH2
Honors Organic Chemistry
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Summary of Bonding Patterns
Atom Valence
Electrons
Positively
Charged Neutral
Negatively
Charged
B
C
N
O
Halogen
Important Note: The bonds shown do not always have to be single bonds
Ex:
Honors Organic Chemistry
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Line-Angle Structures
Often times when we are drawing organic molecules, a large number of atoms are involved and
drawing standard Lewis structures can become somewhat hairy.
e.g. 2-methylpropane (aka isobutane)
A remedy for this is to represent molecules in what is called line-angle format.
There are several important rules to remember when drawing line-angle structures:
1. Every angle and every end of a line that does not have an element symbol represents
a carbon atom.
2. All non-carbon atoms (except hydrogens attached to a carbon) are shown with their
chemical symbol
3. Hydrogen atoms attached to carbon atoms are disregarded.
4. When four lines are drawn from an intersection, an attempt should be made to show
3-D perspective using dashes and wedges.
e.g. 5,5-dimethylhex-3-en-1-ol
becomes
2,4,6-trinitrotoluene
becomes
4-bromo-3-ethylpent-1-yne
becomes
Honors Organic Chemistry
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Worksheet – Line-Angle Structures
For the following structures, if the standard structure is shown, draw the line-angle equivalent. If
the line angle structure is shown, draw the standard equivalent.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Honors Organic Chemistry
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VSEPR Theory
VSEPR:
VSEPR theory is used to predict the 3-D geometry of the terminal atoms around the central atom
of a molecule. VSEPR theory tells us the shape of the molecule and the bond angles to expect.
How to determine the 3-D geometry of a molecule from a Lewis Structure
1. Draw a Lewis structure for a molecule or polyatomic ion
2. Count the regions of electron density around the central atom
a. Any bond (single, double, or triple) counts as one region
b. A lone pair counts as a region
c. The number or regions tells you the “parent shape” or electron arrangement of the
structure
3. If there are any lone pairs around the central atom, the actual shape will be based on the
parent shape, but differ from it in practice.
“Parent
Shape”
Regions of
Electron
Density
Example
Molecule w/ Lewis
Structure
Actual
Shape
Bond
Angles
Drawing Hybridization
of Central
Atom
CO2
BF3
CH4
NH3
H2O
Honors Organic Chemistry
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Parent
Shape
Linear
Trigonal
Planar
Tetrahedron
Trigonal
Bipyramid
Octahedron
Pentagonal
Bipyramid
Honors Organic Chemistry
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Hybridization
Consider the molecule methane, CH4. One carbon atom bonded to four different hydrogen
atoms. Their orbital notations are shown below.
C: ___ ___ ___ ___ ___ H: ___
1s 2s 2p 1s
Hund’s Rule:
Pauli Exclusion Principle:
We know that single bonds are formed by the overlap of two orbitals that each have one unpaired
electron – to be able to form 4 bonds to carbon, one electron will have to be promoted from the
2s to the empty 2p orbital.
C: ___ ___ ___ ___ ___
1s 2s 2p
At present, of the four bonds that carbon is making to hydrogen, there are three “1s overlapping
2p” bonds and one “1s overlapping 2s” bond. From your knowledge of s and p orbitals, draw a
diagram of what this molecule would look like.
There are a couple of problems with the diagram above.
First, experimental evidence shows us that the bond angles for the above molecule are
incorrect – all 4 hydrogen atoms should be equivalently spaced 109.5° from one
another.
Second, all experimental evidence tells us that the four bonds in methane are equal in
energy.
To take into consideration these two problems, a bonding theory called hybridization was
devised
Hybridization:
Honors Organic Chemistry
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Hybridization Continued
sp hybrids: produced from one “s” and one “p” orbital. Two “p” orbitals remain unchanged and
available for π bonding.
Ex: Beryllium in BeCl2 – two sp hybrid orbitals form two σ bonds. Drawing
___ ___ ___ ___ ___ ___ ___ ___
2p Electron 2p Hybridization 2p
___ Promotion ___ ___ ___
2s 2s sp
Ex: Carbon in C2H2 – two sp hybrid orbitals form two σ bonds. Two “p” orbitals remain available for π
bonding. Drawing
___ ___ ___ ___ ___ ___ ___ ___
2p Electron 2p Hybridization 2p
___ Promotion ___ ___ ___
2s 2s sp
sp2 hybrids: produced from one “s” and two “p” orbitals. One “p” orbital remains unchanged and
available for π bonding.
Ex: Boron in BF3 – three sp2 hybrid orbitals form three σ bonds. Drawing
___ ___ ___ ___ ___ ___ ___
2p Electron 2p Hybridization 2p
___ Promotion ___ ___ ___ ___
2s 2s sp2
Ex: Carbon in C2H4 – three sp2 hybrid orbitals form two σ bonds. One “p” orbital remains available for π
bonding. Drawing
___ ___ ___ ___ ___ ___ ___
2p Electron 2p Hybridization 2p
___ Promotion ___ ___ ___ ___
2s 2s sp2
sp3 hybrids: produced from one “s” and three “p” orbitals.
Ex: Carbon in CH4 – four sp3 hybrid orbitals form four σ bonds. Drawing
___ ___ ___ ___ ___ ___
2p Electron 2p Hybridization
___ Promotion ___ ___ ___ ___ ___
2s 2s sp3
Ex: Oxygen in H2O – two sp3 hybrid orbitals with unpaired electrons will form two σ bonds. The two sets
of paired electrons exist as lone pairs. Drawing
___ ___ ___ There is no electron
2p Electron promotion because Hybridization
___ Promotion all orbitals are occupied ___ ___ ___ ___
2s sp3
Honors Organic Chemistry
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Representing Molecules with 3-D Perspective: The Orbital Diagram
When we first learned to draw Lewis structures, we typically drew bond angles that were evenly
spaced in 2-D.
e.g. CH4
Upon the introduction of VSEPR theory, it became clear that the original manner of
representation did not give an accurate reflection of the 3-D shape of most molecules, so we
began drawing molecules with perspective.
e.g. CH4
As we continue to draw more and more complex molecules in 3-D, such as those that involve pi
bonds, their drawings become more and more intricate. Let’s consider a few.
Ethane, C2H6
Ethene, C2H4
Ethyne, C2H2
**Challenge** Allene, H2C=C=CH2
Honors Organic Chemistry
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Worksheet: Hybridization and Lewis Structures
1. For each of the following, predict the hybridization and bond angles for the indicated
atoms.
a) :O:
.. || ..
H – O – C – O - H
˙˙ ˙˙
b) H H
| | ..
H – C – C – O : (-)
| | ˙˙
H H
c) CH3
| (+)
CH3 – N – CH3
|
CH3
d) H H
| |
H – C – C (+)
| |
H H
e) H
.. | ..
:Cl – C = C – C = N – H
˙˙ | |
H H
f)
H – C ≡ C – H
a. Hybridization: _____________ Bond Angle: _______
b. Hybridization: _____________ Bond Angle: _______
c. Hybridization: _____________ Bond Angle: _______
d. Hybridization: _____________ Bond Angle: _______
e.
i. Carbon - Hybridization: _____________ Bond Angle: _______
ii. Nitrogen - Hybridization: _____________ Bond Angle: _______
f. Hybridization: _____________ Bond Angle: _______
2. From question #1, which structures are ions?
3. What type of orbitals are overlapping between the atoms in the following?
a)
H
| ..
H – C = O:
b)
H H
| |
H – C = C = C – H
c)
H
| ..
H – C – O:
| |
H H
Honors Organic Chemistry
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4. Draw Lewis Structures for the following. Remember, hydrogen and terminal
halogens do not make double bonds.
a. CO2
b. CCl4
c. NH4+
d. N2H4
e. NH2-
f. CO3-2
g. NO2+
h. BF3
5. State the hybridization of each central atom from Question #4
a. ______
b. ______
c. ______
d. ______
e. ______
f. ______
g. ______
h. ______
..
6. Use wedges and dashes for σ bonds to draw an orbital diagram of CH3 – C – O:
Draw any “p” orbitals, label bond angles. || |
:O: H
Honors Organic Chemistry
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Worksheet – Bonding and Hybridization
1. For each of the following compounds:
a. Give the hybridization for each atom except hydrogen
b. Give the approximate bond angles for each atom except hydrogen
c. Draw an orbital diagram using lines, wedges and dashed lines for sigma bonds.
Draw the “p” orbital interaction for pi bonds
..I. H3O
+
II. (CH3)4N+
III. CH3 – C = N – H
| H
IV. CH2O
2. For each of the following:
a. Draw the Lewis structure
b. Indicate what type of orbitals are overlapping to form each bond
c. Give approximate bond angles for each atom except hydrogen
..I. CH3 – C ≡ C – C = O
| ˙˙ H
.. II. H2N – CH2 – CN:
III. (CH3)2NH
˙˙
IV. CH3 – CH = C(CH3)2
Honors Organic Chemistry
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3. Predict the hybridization and geometry of each carbon atom in the following anion:
:O: (-)
|| .. CH3 – C – CH2
4. Draw orbital diagrams of the pi bonding in the following compounds. Use lines,
dashes and wedges to show sigma bonds
a. CH3 – C – CH3
|| :O:
.. b. CH3 – C ≡ C – C = O
| ˙˙ H
c. CH3 – CH = CH – CH2CH3 (you may realize there are two ways to do this one,
circle the six coplanar atoms in this molecule)
Honors Organic Chemistry
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Isomerism
In the simplest terms, isomers are compounds with the same ______________ ____________
but a different arrangement of atoms. We will investigate this topic in greater detail in the
future, but for now, it will suffice to introduce a few categories of isomerism and give examples
of each.
1. Structural Isomers – isomers that have different ______-___-_______ bonding
Example: C5H12
2. Cis-Trans Isomers (aka Geometric) – involves either a double bond or a ring;
isomers have the same ______-___-______ bonding, but a different spatial
arrangement about the double bond or ring (because of ___________ rotation)
Example: but-2-ene, CH3-CH=CH-CH3
Extra Practice: Draw all of the isomers of C6H14
Honors Organic Chemistry
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Worksheet – Bonding Part 2
1. 2-pentyne has the formula CH3 – C ≡ C – CH2CH3. Use dashed lines and wedges to
draw a 3-D diagram of this molecule. Draw p orbitals as clouds. Circle the four
atoms that are in a straight line.
2. Which of the following show cis-trans isomerism? Draw the cis and trans isomers of
the ones that do.
a. CH2=C(CH3)2
b. CH3CH=CHCH3
c. CH3C≡CCH3
d.
e. CH3CH = C – CH2CH3
| CH2CH3
Honors Organic Chemistry
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Worksheet – Bonding Part 2 (cont.)
3. State the relationships between the following pairs of structures. Your choices are:
identical compound, cis-trans isomers, structural isomers, totally different molecules.
a. CH3CH2CH2CH3 and (CH3)3CH
b. CH2 = CH – CH2Cl and CHCl = CHCH3
c. CH3 CH3 CH3
\ / and \
CH = CH CH = CH
\
CH3
d. CH3 CH3 CH2
\ / and ||
CH = CH CH3 – C – CH3
e. and
f. and
g. and
Honors Organic Chemistry
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Acids and Bases – Bronsted-Lowry Definition
Bronsted-Lowry Acid:
Bronsted-Lowry Base:
Example reaction:
H :O: H H :O:
| || .. .. | | || .. (-)
H – C – C – O – H + H – N – H H – N – H + H – C – C – O:
| ˙˙ | | (+) | ˙˙
H H H H
Bronsted-Lowry Bronsted-Lowry Conjugate Conjugate
Acid Base Acid Base
The reaction of Bronsted-Lowry Acid and a Bronsted-Lowry Base produces a new acid and a
new base. To distinguish the products from the reactants, they are referred to as the conjugate
acid and conjugate base.
Acids and Bases – Lewis Definition
Lewis Acid:
Lewis Base:
Example reaction:
F H F H
| | (-) | | (+)
F – B + :N – H F – B – N – H
| | | |
F H F H
Lewis Acid Lewis Base
The electron pair involved in a Lewis Acid-Base reaction is shared to form a new covalent bond.
Ex: Using curved arrows, show how acetaldehyde, CH3CHO, can act as a Lewis base.
:O:
|| + H – A
CH3 – C – H
Honors Organic Chemistry
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Equilibrium
Any acid and base reaction is represented by an equilibrium. An equilibrium is a representation
of a reaction that takes into account both the forward and reverse reactions present in a system.
Both forward and backward arrows are written to show this ebb and flow.
Let’s take a look at the reaction of HCl with water:
H2O + HCl H3O+ + Cl
-
An important question to ask here is _________________________________________? That
answer hangs on the following considerations:
1. Which of the two acids (HCl and H3O+) are stronger?
2. Which of the two bases (H2O and Cl-) are stronger?
Having a clear answer to any one of these questions can lead you to know which direction the
equilibrium favors. Equilibrium always drives in the direction of the ________. Since Cl- is
the weaker base and H3O+ is the weaker acid, the equilibrium will move in the direction of the
products.
H2O + HCl H3O+ + Cl
-
Acid Strength – Ka and pKa
Acids vary in terms of their strength, or acidity. Strong acids (such as HCl) will react almost
completely with water, while weak acids (such as acetic acid) react only slightly. The exact
measure of the strength of an acid is given by its acid _________________ constant, Ka.
For the reaction of any acid (shown as HA) with water, the acidity constant, Ka, is
HA + H2O A- + H3O
+
Ka = [H3O+][ A
-] [ ] Concentration in
[HA] mol/L
The stronger the acid in the above equation, the more the reaction favors the ____________.
This results in a large value (greater than 1) for the Ka.
Ka values for acids can vary anywhere from the order of 1015
for the strongest acids to 10-60
for
the weakest. These numbers are unwieldy, so we use the concept of pKa to make the numbers
more workable.
pKa = - log(Ka)
Ka = 10-pKa
Honors Organic Chemistry
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Acid Strength – Ka and pKa - Continued
For the convenience of the numbers, pKa values are usually listed for us to determine the relative
strength of an acid or base.
The lower the pKa value, the stronger the acid. The lower the pKa value of the conjugate acid,
the weaker its conjugate base.
Thus, a very strong acid will have a very ______ conjugate base. This makes logical sense with
what we learned above.
The Relationship Between [H30+], pH Ka and pKa
Chances are that you have heard of the concept of pH before. pH is a measure of the
__________ or _____________ of a water solution, with a low pH corresponding to an acidic
solution and a high pH corresponding to a basic solution.
Although the values for pH and pKa of a strong acid would both tend to be small, and the values
for pH and pKa of a strong base would both be large, the concepts of pH and pKa are inherently
different.
pH = p[H+] = p[H3O
+] = - log[H3O
+]
While the pKa takes into account all of the components of an acid base reaction, pH only focuses
on the concentration of the __________________ (H3O+).
Thus, the pH of a solution __________ change with depending on how much acid or base is
added to the solution (molarity), while the pKa _________.
Example Problem:
A sample of 6.00 g of acetic acid (CH3COOH) is diluted with enough water to make 1 L of
solution. After waiting for equilibrium to become established, the pH is measured to be 2.87.
What is the pKa of acetic acid?
Additional Relationship:
(Henderson-Hasselbalch Equation)
][
][log
cidconjugatea
aseconjugatebpHpKa
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Acid Strength – What makes one stronger than the other?
There are three factors that influence the strength of any particular acid. They all have to do
with an acid’s conjugate base.
1. Electronegativity – The more electronegative the atom, the more likely it is to be
willing to accommodate a ____________ charge. For the elements in the 2nd
period,
this trend is easy to see. Since F is the most _________________ element, its anion
F- should be the easiest to make.
HF > H2O > NH3 > CH4
Acid Strength
2. Size – The relative size of an atom or species, the easier it can accommodate a
negative charge. Atoms or species that are larger allow for charge to be more spread
out, which tends to make ions considerably happier. For the elements in column 7A,
this trend is clearly apparent. As you increase in principle ________ ________, the
diameter of the atoms increases, outer electrons are held less tightly and the atom
becomes more ______________.
HI > HBr > HCl > HF
Acid Strength
3. Resonance – A species’ ability to spread charge around between ___________ atoms
contributes highly to the stability of the _____________ _______. Consider HSO4-,
the conjugate base of sulfuric acid (pKa = -10).
Three additional resonance forms that are all _____________ in energy exist for the
bisulfate ion. This is the major contribution to the stability of the conjugate base, and
in turn, the strength of the acid.
Honors Organic Chemistry
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Acids and Bases – Worksheet
1. Identify the conjugate acid and conjugate base of each of the following. Write
“none” if there is none.
Conjugate Acid Conjugate Base
CH4
NH3
CH3OCH3
CCl4
2. Using your pKa table, predict the products of the following reaction. If there is no
reaction, write NR.
a. CH3COOH + NH3
b. + NaNH2
c. + HCl
3. In which direction do the following equilibriums lie? Explain your choice.
+ -OH + H2O
(+)
CH3CH2NH2 + H2S CH3CH2NH3 + HS-
4. Use your pKa table to suggest an appropriate base to accomplish the following
reaction:
R – C ≡ C – H R – C ≡ C (-)
Honors Organic Chemistry
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Acids and Bases – Worksheet (Cont.)
5. For the following list of compounds:
a. Circle the strongest acid
b. Put a box around the strongest base
c. Show the conjugate acid and base of each compound listed. Write none if there is
none.
d. Is the first compound a strong enough acid to protonate the third? Explain your
reasoning.
Conjugate Acid Conjugate Base
CH3OH
NH3
H2S
SH-
6. Explain why phenol (see below) is more acidic than methanol, CH3OH.
7. 425 mL of an aqueous solution containing 13.0 g of a mystery acid (FW = 142 g/mol)
is found to have a hydronium ion concentration of 0.000743 mol/L. What is the pKa
of this mystery acid?
8. Show the product of a reaction between NH3 and the following secondary carbocation
(see below). Show any formal charges that are required.
NH3 +
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Material Covered on the Unit 1 Test
1. Be able to define and give examples of the all of the key terms on page 2 of this
packet
2. Know the structure and names of all functional groups mentioned in page 2 of this
packet
3. Be able to draw valid Lewis structures for polyatomic ions and organic molecules
4. Be able to assign formal charges to atoms in Lewis structures and also be able to
determine which structures are the major and minor contributors to the resonance
hybrid
5. Be able to predict bond angles and molecular geometry (shape) from Lewis structures
6. Be able to determine the hybridization that carbon, nitrogen, oxygen and sulfur atoms
have undergone in a molecule or ion
7. Memorize the relative order of electronegativities of the following elements:
F, O, Cl, N, Br, S, I, C, P, H.
8. Be able to assign polarity to bonds in Lewis structures
9. Be able to draw Lewis structures and line-angle diagrams for structural isomers if
given a molecular formula
10. Be proficient in the use of curved arrows to show electron movement when drawing
contributing resonance structures
11. Be able to write and interpret condensed structural formulas
12. Draw orbital diagrams of sigma and pi bonding
13. Be able to draw representations of 3-D molecules by using wedges and dashed lines
14. Be able to do calculations between pH, pKa and Ka.
15. Be able to describe the effects of electronegativity, size and resonance on acid
strength – be able to illustrate these with examples.
16. Use curved arrows in acid base reactions
17. Use pKa table to predict products of acid-base reactions and label conjugates in
Bronsted-Lowry reactions
18. Predict directions of equilibria using pKa tables