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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

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

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?

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

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

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

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

AP Chemistry - cyclohexane

2. Consider the molecule cyclohexane, which contains only hydrogen and carbon atoms. a) When a sample is burned in oxygen, 4.822 g of CO(2) and 1.650g of H(2)O are obtained. What is its simplest formula? b) Calculate the mass percent of carbon and hydrogen in cyclohexene. c) How many grams of carbon would you obtain fro

Compounds of Reactions

Explain why compound A reacts 9000 times faster than compound B at 0 degrees, but the two compounds react at the same rate at 103 degrees.

Which of the following molecules has NO net molecular dipole?

1. Which of the following molecules has NO net molecular dipole? a. CH3OH b. CH2O c. CH3Cl d. H2C=CH2 2. Which of the following molecules can hydrogen bond to another of the same compound? a. CH3CH2OCH2CH3 b. CH3CH2COOCH3 c. (CH3CH2)2CHOH d. CH3CH2COCH2CH3 3. What term best describes the relationship betwe

Equation for complete combustion e.g. ethane and cyclopropane

My chemistry book asks the question: Write the balanced equation for the complete combustion of each of the following compounds: a. ethane, C2 H6 The book has the answer which reads: 2C2h6 + 7O2 I don't understand where the formula for 7 02 b. cyclopropane I understand the formula C3H10 but I do

Organic Chemistry: Alcohols

Hi, I need some assistance with this organic chemistry concept. Could you show me how to draw all the alcohols that have the molecular formula C5H11OH. I also need assistance assigning the names to each compound and explaining if they are primary, secondary, or tertiary alcohols.

Ionic Activities

Find the activity(not the activity coefficient) of the (C3H7)4N+ (tetrapropylammonium) ion in a solution containing 0.005 M (C3H7)4N+Br- plus 0.005 M (CH3)4N+Cl-. Activity coefficients : Ionic strength .001 .005 .01 .05 0.1 (C3H7)4N+ : .966 .931 .912 .85 .82 CH3)4N+:

Drawing Meso Forms

Which of the following compounds have a meso form? (a) 2,3-Dibromopentane (b) 2,4-Dibromopentane (c) 2,3-Dibromobutane

Conversions

1.) is 47.8 ng/L = 0.0478ppb? and if so would that above concentration be above 10,000 ug/L (what would this be in ppb) 2.) is 6.77 ng/m^3 = 0.0066 ppb? an if so, would that exceed 0.5-5g/Kg for a 70 kg person (which is a lethal concentration) (and what would this be in ppb) and would that exceed Lethal co

Enantiomers and Order of Elution

The enantiomers (R and S forms) of the following chiral alcohols need to be separated by a suitable CHIRAL SEPARATION method. What is a reasonable approach that will yield the separations of the two isomeric alcohols and their enantiomers. Rationalizing the approach used on the basis of chiral recognition mechanism. What will

Colligative Properties

An unknown organic compound is a nonelectrolyte known to be composed of C, N, O, and H. Combustion analysis showed that it contained 67.3% C, 4.62% N, and 6.93% H. A solution made by dissolving 1.20 g of the unknown compound in 25.0 g of benzene had a freezing point of 4.7 degrees Celsius. Determine: a) the empirical formula b

Steps in the synthesis of compounds

The professor wants us to do the following: Outline all steps in the possible synthesis of each of the following compounds from benzene and / or toluene, using any necessary aliphatic or inorganic reagents. Assume a pure para isomer that can be separated from an ortho/para mixture a) ethylbenzene b) phenyacetylene c) iso