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Organic Chemistry

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

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

Dehydrohalogenation

Prepare styrene (C6H5CH=CH2) by dehydrohalogenation of either 1-bromo-2-phenylethane or 1-bromo-1phenylethane using KOH in ethanol. A) Which halide would be best as starting material to give the better yield of alkene? B) Explain your answer in a.

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+:

Distinguishing between Organic Molecules

Question: What chemical tests might be used to distinguish between: pentanal and 2-pentanone, between benzyl alcohol and diphenylmethanol? I believe that the tests to distinguish pentanal and 2-pentanone can be: NMR spectrometry and a 2,4 dinitrophenylhydrazine test. The tests to distinguish benzyl alcohol and diphenylmethanol c

Diacetylferrocene

In the formation of diacetylferrocene, the product is always the one in which each ring is monoacetylated. Why is no diacetylferrocene produced in which both acetyl groups are on the same aromatic ring?

Propyl p-tolyl ether lines and carbons

There are only four lines in the aromatic region of the fully 1H decoupled 13C NMR spectrum of propyl p-tolyl ether (110-160 ppm), yet there are six aromatic carbon atoms. Explain.

Drawing Meso Forms

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

Specific Rotation of a Compound

A sample of 150 mg of an organic compound is dissolved in 7.5 mL of water. The solution is placed in a 20-cm polarimeter tube and the rotation measured in a polarimeter. The rotation observed was +2.676 degrees. Distilled water, in the same tube, gave a reading of +0.016 degrees. Calculate the specific rotation for the compound.

TLC and Azobenzene: Example Problems

a) Discuss what you would observe after elution and visualization of a TLC plate having made the following mistakes in carrying out the analysis. 1. The solvent level in the developing jar was higher than the original line on which the samples were spotted. 2. Too much sample was applied to the TLC plate. b) Over the y

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

Geometric isomers illustration

This is more of a theoretical question I think. Co(NH3)5ClBr has two compounds for that one formula. My question is how would I be able to demonstrate that the two compounds are different and how would I be able to explain what kind of isomerism it illustrates?

Accounting for the contrast with nitration

Upon nitration, 1-naphthol (1-hydroxynaphthalene) yields 2,4-dinitronaphthol, while 1-nitronaphthalene yields, 1,8-dinitronaphthalene and 1,5-dinitronaphthalene. How do you account for this contrast?

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

Chemistry

Do the following, starting from alcohol that contains four or less carbon atoms and from benzene and toluene, outline how the following can be synthesized: a) 2,3-dimethyl-2-butanol b) 2-bromo-2methyl hexane c) 1,2-diphenyl-2-propanol d) 1-parabromophenyl-1phenal-1propanol

pH Calculation of a Solution Formed During Titration

Calculate the pH of the solution formed during a titration upon adding 35.0 ml of a standard .150M NaOH solution to: a. 15.00 ml of .200 M CH3COOH Ka = 1.8 x 10^-5. b. 36.0 ml of .100 M malonic acid, (H2M) (Ka1 = 1.42 x 10^-3, ka2 = 2.01 x 10^-6