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Organic Chemistry

Unsaturated lipids in cephalin

1. What are the ingredients of a cephalin? 2. Which fatty acid is always unsaturated in a cephalin? Why? 3. What is the enzyme system used in the formation of the prostalandins and thromboxanes? 4. Would you expect sodium ions (Na+) to be able to pass easily into a cell through bi-layer membrane wall? Why or Why not?

Organic Chemistry: Spectroscopic and Chemical Tests

Please answer the following questions. 1. Using sketches, demonstrate why the addition of HCN to 2-butanone yields a racemic mixture of chiral products. Circle the chiral carbon in each product. 2. Describe spectroscopic or chemical tests to distinguish between the following pairs of compounds: a. 2-pentanone vs 2-pentano

Lipids - Methanol, Ethanol & 1-Propanol Reactions

Methanol, Ethanol, & 1-Propanol 1) How would you sketch these three alcohol molecules? 2) What is each of their polarity? 3) What differences might you expect in the comparative solubility of each of them in lipids? WHY??? 4) If you were to add 2 drops of sheep blood to each of these alcohols (about 1/3 of a small te

Organic Chemistry and Structural Properties

In the mass spectrum of butylbenzene, the base peak occurs at m/z a. 134 b. 119 c. 105 d. 91 The number of mono-bromination products of p-xylene is a. 1 b. 2 c. 3 d. 4 Which of the following compounds has the lowest boiling point? a. p-dichlorobenzene b. o-dichlorobenzene c. m-

Aromaticity and Hybridization

I need some help with answering these questions: (See attached file for full problem description and structural formulas) 1. Predict whether the molecule would be expected to show aromatic character or not. Explain your answer. 2. What is the hybridization of the nitrogen atom in sulfathiazole? 3. Assuming that the sulfur

Mass and Infrared Spectra for Hydrocarbons

6. The mass spectrum and the infrared spectrum for an unknown hydrocarbon are shown below. From this information, suggest a structure for the hydrocarbon. Indicate on the spectra how your structure fits the data. (See attached file for full problem description)

Infrared and Mass Spectroscopy

4. Infrared Spectroscopy (a) Deduce a possible structure for the compound with the following major IR absorptions. Explain your choice based on the IR absorptions, indicating the absorptions on your molecule. C4H8O: 3000, 2850 (weak), 2715 (weak), 1730 (strong) cm^-1. (b) How could you use IR spectroscopy to distinguish betw

Organic oxygen compounds and possible isomers for Methanol

What are the possible isomers for Methanol, 1-Propanol, & 1-Pentanol? Are Methanol, 1-Propanol, & 1-Pentanol soluble in water and also in hexane? Why or why not? Why isn't it possible to make a ketone molecule out of a methanol or ethanol molecule? Is it because they have been oxidized?

Identifying an unknown hydrocarbon

Is it possible to identify what the hydrocarbon is with just knowing the volume of it (9.61 ml), the mass (7.669 g/ml), density (0.798 g/ml)? Under tensor lamp, in ambient light, and in dark light there was no color noticed. It smelled somewhat like gasoline maybe and was smoky as far as combustion characteristics. Boiling poin

Organic Chemistry Problems - Asorption

Absorption of UV-visible energy by a molecule results in: a. vibrational transitions b. rotational transitions c. proton flips d. electronic transitions. 2. Which of the following compounds absorbs the longest wavelength of UV-visible light? a. 2-butene b. 1,4-hexadiene c. 1,3-hexadiene

Benzene as an Organic Solvent

Benzene is a organic solvent with the formula, CB6BHB6B. It boils at 80.1 C and melts at 5.5 C. Benzene's density is 0.88 gm/ml, its heat of vaporization is 20.0 KJoules per mole, its heat of fusion is 10.0 KJoules per mole, its heat capacity is 0.50 KJoules per mole-degree C for liquid benzene, 0.25 KJoules per mole-degree C fo

Isomeric Products Isolated from Free-radical Chlorination

Some isomeric products were isolated from the free-radical chlorination of (R)-sec-butyl chloride. a) Draw stereochemical structures of the 1,2-, 2,2, and 1,3- dichlorobutanes obtained in this way. Give the proper R/S specification of 1,2 and the 1,3-dichlorobutanes. b) Which of these fractions as isolated will be optically act

Carbohydrates with D and L Series

Please see the attached for diagram. What is the number of carbon atom that determines whether the carbohydrate shown below belongs to the D series or to the L series? a. 1 b. 2 c. 3 d. 4 e. 5

mutarotation of glucose

Please see attached The fact that glucose undergoes mutarotation is best explained by a. righ flipping between nonequivalent chair conformations by the b-pyranose form. b. interconversion of the alpha and beta pyranose forms. c. interconversion of aldehyde and enol forms d. interconversion of aldehyde and ketone forms e.

Carbohydrates and fructose

Each of the following statements about fructose is correct except one. Which statement is incorrect? a. Fructose is a stereoisomer of glucose b. Fructose has six carbon atoms c. Fructose is a monosaccharide d. Fructose is a ketose

Carbohydrates - glucose properties

Each of the following statements about glucose is correct except one. Which statement is incorrect? a. Glucose is an aldose b. Glucose is a hexose c. There are 14 diastereomers of glucose (in its open-chain form). d. Glucose is a monosaccharide e. Glucose is a stereoisomer of ribose.

Aldehydes and Ketones

Show that you know how to make the compound shown int he attachment by identifying the first step in its synthesis from 1-bromobutane. With which of the following would you treat 1-bromobutane in the first step?

Chemical Reaction Calculations

1. Unbalanced equation SOCL2(1) + H2O(1) --- SO2(g) + HCl(g). How many molecules of H2O can 35.0 grams of thionyl chloride remove? 2. An experiment that led to the formation of the new field of organic chemistry involved the synthesis of urea, CN2H40, by the controlled reaction of ammonia and carbon dioxide: gaseous ammonia +

Organic Food and Organic Chemical

89. A) We often hear the terms organic, natural, and chemical in the media. Organic and natural are usually used to imply that a product is "healthy" and/or "environmentally friendly" while chemical often implies negative implications for health and for the environment. In your opinion, are these implications justified? Us

Stereochemistry and Chirality

Which one of the following is chiral? a. 1,1-Dibromopropane b. 1,2-Dibromopropane c. 1,3-Dibromopropane d. 2,2-Dibromopropane e. 2-Bromo-2-chloropropane

Aromatic compounds and Nitration

Which one of the following compounds undergoes nitration of its aromatic ring(electrophillic aromatic substitution) at the fastest rate: Benzene, Chlorobenzene, Nitrobenzene, Anisole, or Ethylbenzene?

Aromatic compounds - Dinitration of Biphenyl

(See attached file for full problem description) The structure of biphenyl and the numbering scheme used in naming its derivatives are indicated below. What is the major product obtained on dinitration of biphenyl?

Specific Rotation of (-)-epinephrine/ and Calculation of enantiomeric excess

1. A solution of 0.5g (-)-epinephrine dissolved in 10mL of dilute HCl was placed in a 20-cm polarimeter tube. Its optical rotation in sodium line (light wavelenth) was -5.0 degrees at 25 degrees Celsius. What is the specific rotation of the (-)-epinephrine? 2. Calculate the enantiomeric excess (e.e.), a measure of optical p