1.1. Your 2-(1-hydroxyethyl)benzofuran was enriched in one enantiomer. Assuming that
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generally cannot be made to produce either enantiomer as desired, use your knowledge of organic
reactions to design a reaction sequence to convert your sample to the other enantiomer. Show
reaction(s) and appropriate reagents.
2. Consider applying biocatalytic reduction with carrots to the following two ketones: tert-butyl
methyl ketone, and 3-hexanone. Which would you expect to give higher enantioselectivity in
biocatalytic reduction? Explain your answer.
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6.AP Chem AB FRQ
Question 1
A sample consisting of 50. mL of 0.400 M solution of the acid, HClO4, is titrated
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titrated with a 0.200 M solution of the base, LiOH.
Write the balanced chemical reaction for neutralization reaction:
HClO4 (aq) + LiOH (aq) → LiClO4 (aq) + H2O (l)
Write the NET ionic equation for the neutralization reaction.
OH⁻ (aq) + H⁺ (aq) → H2O (l)
Compute the pH of the titration solution. Show your work
i) before any of the base is added
ii) after 25. mL of base is added
iii) after 50. mL of base is added
A student performs the titration with the same chemicals but with smaller volumes of each chemical . Which of the following titration curves could represent the titration. Explain
A because this entails a strong acid and a strong base.
Question 2
A student performs a titration of an unknown acid with a strong base and gets the following titration curve:
a) The student consults the list of pKa of acids shown below. If the acid is listed in the table below, which is the most likely identity of the unknown acid? Explain.
Acid
Ka
HF
7.2 x 10-4
CH3COOH
1.8 x 10-5
H2CO3
4.3 x 10-7
HBrO
2.0 x 10-9
The unknown acid is HBrO because the calculated Ka is in between 50^-4 and 50^-6 and 2.0 x 10^-9 lies in between them.
b) What is the initial molarity of the acid?
10^-3 = 0.001M
Question 3
a) Describe the components and the composition of an effective buffer solution. Explain how the components of the buffer allow the buffer to maintain its pH.
An effective buffer solution has a weak acid and its conjugate base or a weak base and its conjugate acid. A buffer solution is most effective when the ratio of its component concentrations is close to 1, also when the pH is equal to the pka of the acid.; The components of the buffer allow the buffer to maintain its pH because buffers can absorb excess H+ions or OH– ions.
An employer is interviewing four applicants for a job as a laboratory technician and asks each how to prepare a buffer solution with a pH of 5.0. The following constants may be helpful: hydrazoic acid, pKa = 4.74 Boric acid, pKa = 9.23
Archita A. says she would mix equal molar solutions of hydrazoic (HN3) and sodium azide (NaN3) solutions.
Bradley B. says she would mix equimolar Boric acid (H3BO3) and HCl solutions.
Carlos C. says he would mix equimolar Boric Acid (H3BO3) and sodium dihydrogen borate (NaH2BO3) solutions.
Delia D. says he would mix equimolar hydrazoic Acid (HN3) and NaOH solutions.
b) Which of these applicants has given an appropriate procedure? Explain your answer
Delia because she is using Sodium hydroxide which results in a pH of 5. NaOH is a strong base and in order to have an effective buffer a weak acid must be incorporated which is the HN3.
c) Explain what is wrong with the erroneous procedures.
The rest all incorporate a strong acid and a strong base or a weak acid and a weak base which don’ result in an effective buffer.
d) The applicants have access to the 1 Liter volumes of each of the solutions listed above. They have access to graduated cylinders. In order to make 1.0 Liter of the correct 5.0 buffer solution, what volumes of the two chemicals must be mixed?
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8.Question 1: What is a player’s « reaction function » in a Bertrand game ?
Question 2: What is a subgame
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subgame perfect Nash equilibrium?
Question 3: In which situations should we need the mixed extension of a game?
Question 4: Find, if any, all Nash equilibria of the following famous matrix game:
L R
U (2,0) (3,3)
D (3,4) (1,2)
Question 5: What is the difference between a separating equilibrium and a pooling equilibrium
in Bayesian games?
Question 6: Give another name for, if it exists, the intersection of the players’ best-response
« functions » in a game?
Question 7: assuming we only deal with pure strategies, the Prisoner’s Dilemma is a situation
with:
No Nash equilibrium One sub-optimal Nash equilibrium
One sub-optimal dominant profile No dominant profile
Question 8: If it exists, a pure Nash equilibrium is always a profile of dominant strategies:
True False
Question 9: All games have at least one pure strategy Nash equilibrium:
True False
Question 10: If a tree game has a backward induction equilibrium then it must also be a Nash
equilibrium of all of its subgames:
Tr
2/2
Question 11: The mixed Nash equilibrium payoffs are always strictly smaller than the pure
Nash equilibrium payoffs:
True False
Question 12: Which of the following statements about dominant/dominated strategies is/are
true?
I. A dominant strategy dominates a dominated strategy in 2x2 games.
II. A dominated strategy must be dominated by a dominant strategy in all games.
III. A profile of dominant strategies must be a pure strategy Nash equilibrium.
IV. A dominated strategy must be dominated by a dominant strategy in 2x2 games.
I, II and IV only I, II and III only II and III only
I and IV only I, III and IV only I and II only
Question 13: A pure strategy Nash equilibrium is a special case of a mixed strategy Nash
equilibrium:
True False
Question 14: Consider the following 2x2 matrix game:
L R
U (3,2) (2,4)
D (-1,4) (4,3)
The number of pure and mixed Nash equilibria in the above game is:
0 1
2 3
Exercise (corresponding to questions 15 to 20 below): assume a medical doctor (M)
prescribes either drug A or drug B to a patient (P), who complies (C) or not (NC) with each of
this treatment. In case of compliance, controlled by an authority in charge of health services
quality, the physician is rewarded at a level of 1 for drug A and 2 for drug B. In case of noncompliance, the physician is « punished » at -1 level for non-compliance of the patient with
drug A and at -2 level for non-compliance with drug B. As for the compliant patient, drug A
should give him back 2 years of life saved and drug B, only 1 year of life saved. When noncompliant with drug A, the same patient wins 3 years of life (due to avoiding unexpected
allergic shock for instance), and when non-compliant with drug B, the patient loses 3 years of
life.
Question 15: You will draw the corresponding matrix of the simultaneous doctor-patient game.
Question 16: Find, if any, the profile(s) of dominant strategies of this game.
Question 17: Find, if any, the pure strategy Nash equilibrium/equilibria of this game.
Question 18: Find, if any, the mixed strategy Nash equilibrium/equilibria of this game.
Questions 19 and 20: Now the doctor prescribes first, then the patient complies or not: draw
the corresponding extensive-form game (= question 19) AND find the subgame perfect Nash
equilibrium/equilibria (=
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