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CH 235-2F
Worksheet 6-Exam 2
September 29, 2014
Short Answer:
1.
What are the three definitions for acids/bases? Give an example of each. Which
one is most useful for organic chemistry?
2. Fill in the table below regarding factors that affect acidity/basicity.
Factor
s character
Arrange the following in
order of most s
character to least s
character: sp3, sp2, sp
Size
Follow this trend when
going down a
__________________.
Which is larger, Iodine
or bromine?
Electronegativty
Follow this trend when
going across a
__________________.
True or False: HF is a
weaker acid than NH3.
Inductive Effect
This involves the pulling
of electron density
through
_____________
How does distance
effect this?
____________.
Why does more s
character mean a strong
acid/weaker conjugate
base?
According to your
answer in 3C, is HI a
stronger acid than HBr?
True or false: more
electronegative atoms
will result in more of an
inductive effect.
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Factor
Resonance
This trend allows for
__________________
of charge.
Draw the resonance
structure for the
conjugate base of
CH3COOH
General Question: Does
equilibrium favor the
strong acid/strong base
or the weak cid/weak
base?
3. What is a nucleophile? What is an electrophile? Give examples of each. How do you
determine which species is a nucleophile/electrophile given a reaction?
4. For each reaction below, determine which species is the nucleophile and which
species is the electrophile.
H20 + NH3
CH3COOH + H2O
HPO42- + NH4+
NH4+ + OHCH3COO- + H3O+
NH3 + H2PO4-
Matching
A.
B.
C.
D.
E.
F.
G.
H.
Low pKa
High pKa
Low pKb
High pKb
High Ka
Low Ka
High Kb
Low Kb
_________1. Strong Acid
_________2. Strong Base
_________3. Weak Acid
_________4. Weak Base
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5. Arrange the following in order of increasing acidity: HS, HF, HCl, HSe What trend
did you use?
6. Arrange the following from weakest to strongest conjugate base (I have shown the
acid):
Multiple Choice
1.
Which of the following statements is true?
A. HCl is a stronger acid than HI.
B. A molecule that can delocalize charge due to resonance is a more stable conjugate
base than one with no resonance structures.
C. A carbon with spy hybridization has more s character than a carbon with sp
hybridization.
D. HF is a weaker acid than H2O.
E. Both B and D.
2. Which of the hydrogens indicated below is most likely to be removed in an acid/base
reaction?
A.
B.
C.
D.
Green Arrow
Blue Arrow
Yellow Arrow
Red Arrow