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Organic Chemistry

Qualitative Observations of Organic Liquids

1) What do understand by the terms a) Empirical Formula b) isomerism and what conclusions can you draw from the following observations about the chemical nature of the organic liquid D? a) D (relative molecular mass 72 ) has the following persentage composition by mass: Carbon 66.7, hydrogen 11.1, oxygen 22.2 b) D gives an

Organic Chemistry and HNMR Spectrum

1. A proton that absorbs radio frequency radiation at higher field strength will appear _____ in a 1H NMR spectrum. a. at 0 ppm b. downfield (away from TMS) c. upfield (closer to TMS) d. at 7.27 ppm just like CDCl3 2. The carbonyl peak of benzaldehyde appears as a very strong and intense peak at 1703 cm^-1. Normally the

C-13 NMR and GC of 3-Pentanol and 2-Pentene

A) Why is GC not able to distinguish between the trans vs. cis-2-pentene products? b) Explain why the 3-pentanol 13C-NMR spectrum contains three peaks while the trans and cis-2-pentene spectra contain five peaks (note that 13C-NMR gives a peak for each unique carbon, i.e. identical carbons show up as the same peak).

Evaporation and Its Effects on PCP and Cresol

We are asked to explain the phenomena of how 1 gram of liquid water at 35 degrees C (as in a pond or lake) evaporating into an overlying air mass at a temp of 65 degrees C and a relative humidity of 50%. What actually causes the evaporation of water and how can this be calculated in this instance?? What is the vapor pressure

Organic Chemistry

1. Draw structural diagrams and give the names for the isomers of pentane. 2. When 2-butene reacts with hydrogen chloride gas, only one product is detected, whereas when 1-butene reacts similarly, two products are usually found. Explain this. 3. Geometric isomers exist in the alkenes but not in the alkynes. Explain why.

NMR Tree Diagram

In this problem the H NMR spectrum of styrene oxide shows that protons 1, 2, and 3 all have different chemical shift values. Proton 2 is coupled to both proton 1 (J= 5.8 Hz) and proton 3 (J=2.5 Hz). Draw a scale tree diagram and your best rendering of the resulting peaks for proton 2. See attached file for full problem desc

Butane Combustion and Developed Formulas

1) How many grams of CO2 can you obtain from the combustion of 280 g of butane? 2) Write the developed formula of the following compounds (they are in Spanish) a) 2Chlorine 2metil 1hexanol b) 3 hidroxipentanoico c) Etanoato de metilo d) Metal propel amina e) 3 hidroxi 1metil benceno 3) Assign the name and complete wi

Assign formal charges to each atom

Assign formal charges to each atom in the attached file. Cross out the configurations that are not reasonable, and provide an explanation (eg large charge, incomplete octet, octet exceeded).

Matching structures to descriptions

Match a structure from the attachment to: a. an octapeptide with a C-terminal valine. b. an amino acid in its zqitterionic form. c. a polypeptide which gives four fragments on treatment with chymotrypsin d. the product of an edman degradation e. a carboxyl-protected amino acid. f. a peptide coupling reagent 36. sm

Organic Chemistry Problems: Compound Relationships

What is the correct structure for D-glucopyranose? What is the relationship between the following compounds? a) anomers b) meso compounds c) enantiomers d) equivalent structures What is the relationship between the following compounds ? a) anomers b) meso compounds c) enantiomers d) equivalent structures

NMR and MS techniques

What are the advantages of NMR and MS write one compound which you can identify using each of these techniques.


(See attached file for full problem description) p_Ethyl aniline is treated with NaNO3 in HCl to generate the diazonium salt. For the first two, show what reagents are necessary to convert the salt to the products shown below. For the third, show what product is obtained. Synthesize the following compounds using the startin

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

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

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

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