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Acid and Base Organic Chemistry

Variation of pKa values among benzoic acids

A) Four benzoic acids are in the attached file along with four pKa values. Assign a pKa to each acid, and briefly explain the basis for your order. b) While o-nitrobenzoic acid and p-nitrobenzoic acid differ significantly in pKa (as seen in part a), o-nitrophenol and p-nitrophenol do not; their pKa's are essentially the same

2-methyl-1,3-cyclohexanedione structures and reactions

Using 2-methyl-1,3-cyclohexanedione, shown in attached file, a) write the structures of all possible enol forms b) write the product of reaction with excess D2O and catalytic amounts of acid c) write the product of reaction with one mole of Br2 in acetic acid d) write the product of reaction with formaldehyde [methanal] wit

Volume and pressure problems

6. One of the treatments for gangrene and "the bends," is hyperbaric oxygenation. This occurs in a chamber in which oxygen is used at higher-than-normal pressures. How many grams of oxygen are required to fill a 4.50 x 103 liter hyperbaric chamber at a pressure of 225 cm Hg and at 62° F? If the same quantity of oxygen was pumpe

Organic chemistry problems

1.What is the change in pH when 0.005 moles of HCl is added to 0.100 L of a buffer solution that is 0.100 M in CH3CO2H and 0.100 M NaCH3CO2? The Ka for acetic acid is 1.8 x 10 -5. 2. What is the resulting pH when 0.005 moles of KOH is added to 0.100 L of a buffer solution that is 0.100 M in H2PO4- and 0.100 M HPO4 2- and the

Categorization of sugar and steroids

(See attached file for full problem descriptions) A. Categorize the attached sugar diagram as D or L. Draw its Haworth structure as the beta anomer. B. Draw a triglyceride with a chiral carbon which contains two molecules of stearic acid (18 carbons) and one molecule of oleic acid (18 carbons, one double bond at C9). Circ

Elimination reaction

a. Comment of the fact that erythro-2,3-dibromo-3-phenylpropanoic acid undergoes elimination by an E1 pathway in water solvent, but by and E2 pathway when acetone is used as the solvent. b. A benzylic carbonation is generated under the water solvent would the presence of a para CH3O- group on the benzene ring increase or dec

Carboxylic acid and Fischer esterification

The reaction of carboxylic acid with an alcohol in the presence of acid is termed Fischer esterification. (See attachment for diagram). 52. The nucleophile in this reaction is _______. 53. Compound C functions as ______ in this reaction. a) a base scavenger b) a solvent c) a catalyst d) a neutralizer 54. Fischer est

Organic Chemistry: Synthesizing Compounds

Please answer the following questions. Draw the synthesizing of the compounds. 1. Starting with toluene, prepare 2-bromo-4-nitrotoluene. 2. Starting with toluene, prepare 2,4,6-trinitrobenzoic acid. 3. Starting from benzene, prepare p=chlorostyrene. 4. p-Bromotoluene reacts with potassium amide to give a mixture of m- and

Finding unknown compounds

11. A low-melting solid A was isolated, which combustion analysis showed had composition C9H10O. The substance gave a precipitate when treated with 2,4-dinitrophenylhydrazine solution. Furthermore, when reacted with iodoform reagent, a yellow precipitate of CHI3 was observed. Acidification of the alkaline solution from the iodo

Stretching Vibration in Alcohols and Amides

Please help with these questions on stretching vibration: 5. The antisymmetric -CH2-CO-O- stretching vibration in carboxylic acids is heavily mixed with the in-plane bending mode of the O-H group. In alcohols these two vibrations seldom show evidence of mechanical coupling. Explain. 8. The hydroxylamine I can be oxidized

Synthesis of cyclic carboxylic acid anhydrides

I am having trouble understanding why when maelic acid is heated to about 100 C it forms maelic anhydride but fumaric acid requires a much higher temp 250-300 before it dehydrates. Then in addition it only forms maleic anhydride?

Amines Acidification with Ammonia

If you add 15 drops of 6M HCl (a source of H+) to a mixture of 10 drops of 6 M ammonia solution and 1 dropperful of demineralized water, what would the following be: 1) pH 2) solubility 3) observed chemical reactions that would occur If you were to re-basify the solution by adding 20 drops of 6 M NaOH (which is a source of

Amines, demineralized water, and triethylamine

What is the pH of 10 drops of 6M ammonia solution in a dropperful of demineralized water? How does the reaction between ammonia and water explain the measurement of the pH? What is the pH of 10 drops of triethylamine in a dropperful of demineralized water? How does the reaction between triethylamine and water explain th

Aspirin, salicylic acid

1. When making aspirin, if you had 3 g of salicylic acid, what would the moles of salicylic acid used be? How would you calculate that? 2. What would the theoretical yield in moles be and how would you calculate that? 3. What would the theoretical yield in grams be and how would you calculate that?

Grignard Reagents and Carbonyl Compounds

3. A novice chemist wishes to prepare 1-methyl-1,4-cyclohexanediol from the compound shown below. He wishes to use an appropriate Grignard reagent in the synthesis. Was the chemist successful? Explain why or why not. (see attached file for diagram) 4. Synthesize the following compounds using the indicated starting materials.

Solubility in hexane

Is methanol soluble in hexane? Why or why not? Is 1-propanol soluble in hexane? Why or why not? What is the sketched formula for ethyl methyl ester and is it an isomer of butanoic acid? If not, what is the isomer of butanoic acid?

Stretching Vibration Calculations

I need some help with these acid and base chemistry questions. 1. The Anti-symmetric -CH2-CO-O Stretching Vibration in carboxylic acid is heavily mixed with in plane bending mode of the OH group. In alcohol these two vibrations seldom show evidence of mechanical coupling. Explain. 2. Conjugation of the functional group i

Acid and base: Structures, Reactions, and NMR Spectrums

1. If 3-bromo-1-propanol is treated with NaOH, a compound of molecular formula C3H6O is formed. Suggest a structure for this product. 2. What product(s) would you expect to form when tetrahydrofuran is treated with excess hydroiodic acid (HI)? 3. Write a suitable mechanism for the cleavage of butyl isopropyl ether with HI

Hydration and Hydrogenation Reactions

Give and name the products when 3-t-butyl 2,4-dimethyl 1-hexene reacts with the following (assume the proper catalysts are present): 1) Water 2) Hydrogen gas

Fischer Estrification Equilibrium

I need some help answering questions on Fischer Esterification equilibrium, where in my lab I am using the reagents of 2-phenylacetic acid and ethanol: The equilibrium of Fischer esterification reactions in general is slightly towards product formation. The equilibrium can be made more favorable for product formation by all o

Explanation of a fischer esterification reaction

Choose the starting reagents: 2-phenylacetic acid and ethanol. Return to the lab and build the experimental set up. Use a heater, condenser and N2 gas. Add the reagent, H2SO4. In this experiment (a) which group in the acyl compound is being substituted and (b) what is the substituting group? a. (a) the carbonyl group of 2-

Fischer Esterification Reaction

I need some help with concepts in the esterification reaction, especially on this question: The Fischer Esterification is really an example of: a. A nucleophilic acyl substitution reaction b. An aldol condensation reaction c. An elimination reaction (either E1 or E2) d. An electrophilic addition reaction e. A conjugated a

Acid-Catalyzed Condensation of Ethanol

I need some help with this question, see attached jpg for better formula representation: Formation of ethyl acetate by acid-catalyzed condensation of ethanol and acetic acid involves attack by: a. CH3CO2- on CH3CH2OH b. CH3CH2O- on CH3CO2H c. CH3CO2H on CH3CH2OH d. CH3CO2H on the protonated form of ethanol (CH3CH2OH2+) e.

Carboxylic acid amide conversion

A carboxylic acid is best converted to its amide by reaction with: a. NaNH2 in liquid ammonia b. Aqueous ammonia, 25 degrees Celcius c. SOCl2, followed by excess aqueous ammonia d. CH3OH, followed by reaction with NH2OH

Bromine addition to trans-cinnamic acid

During bromine addition to trans-cinnamic acid, why is it necessary to maintain excess bromine in the reaction mixture and how can you tell there is an excess of bromine?

Derivatives of butanoic acid

Indicate how a butanoic acid can be converted to an a) acid chloride; b) acid anhydride; c) an ethyl ester, and d) an N-methyl amide. Give the reagents that would be used. Then indicate how each of these derivatives could be converted back to butanoic acid under both acidic and basic conditions.

Acid Base Reaction Scheme

1. Offer an explanation of why anthracene preferentially forms a Diels-Alder adduct at 9,10 positions. 4. Outline a synthetic reaction scheme for the preparation of triphenylmethanol from: a. Methyl benzoate b. Diethyl carbonate

Conversion of Nerol into Alpha-Terpinol

Suggest a mechanism (using arrows/arrow pushing and intermediates if applicable) for the conversion of nerol (C10H18O) into alpha-terpineol (C10H18O) in the presence of dilute H2SO4. Please see attached .jpg for start and end product structure.