Explore BrainMass
Share

Explore BrainMass

    Organic Chemistry

    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

    Oleic Acid Chemical Formulas

    The chemical formula for oleic acid is CH3(CH2)7CH:CH(CH2)7COOH. What would be a balanced equation for the complete oxidation of one mole of oleic acid?

    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.

    Information About Sulfur

    Question: How many isotopes does sulfur have and what are the natural abundances of the four most abundant isotopes?

    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

    Balancing chemical equations

    I am having trouble trying to understand how the following dissociation equation balances Could you please explain this to me as my working out has it not to balance Thank you Ba(OH)2 + H2O-----> Ba+2 + 2OH-

    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?

    Stability and (R or S) Configuration

    (a) Which conformer, K or L is predicted to be more stable? Explain your answer (Note: a methoxy group is smaller than a methyl group). (b) Assign the absolute (R or S) configurations for each of the chiral carbons in carbohydrates M and N. Are either of these compounds optically active? Briefly explain your answer.

    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?

    Conformers

    Which conformer, K or L is predicted to be more stable? Explain your answer (Assign the absolute (R or S) configurations for each of the chiral carbons in carbohydrates M and N. Are either of these compounds optically active? Briefly explain your answer. Please see the attachment.

    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

    Solve: Naming a Ketone

    Please view the attachment to view the compound in question. Solve this question: What is this ketone called?

    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

    Calculating the Distribution Ratio

    Question: You are given an organic acid that has a pKa value of 5.0 and a distribution constant of 3 between H2O and Toluene. Calculate the distribution ratio of this compound at pH=6.

    Partial pressure of CO2 in blood.

    The plasma (HCO3-) of an individual living at a high elevation is 18.5 meq/L. If this concentration of bicarbonate fully compensates the decrease in PCO2 found at the higher elevation, the PCO2 must be: 15, 18, 21, 31, or 37 mm Hg.

    Nomenclature

    Please see the attached file for full problem description.