Explore BrainMass
Share

Organic Chemistry Bonding

Strain or Steric energy

Please draw the structures neatly and clearly and follow directions. If you have a Chem drawing program (i.e. ChemDraw, Chem3D), I will increase the credit, if not please draw them out by hand. Strain or Steric energy (a) Choose an alkene having cis and trans isomers and draw one of these (give name of alkene also).

Heating Organic Acids

When maleic acid is heated to about 100C it forms maleic anhydride. However, fumaric acid requires a much higher temperature (250-300C) before it dehydrates. In addition, it forms only maleic anhydride. Explain.

Resonance structures and bond lengths and types in molecules

(See attached file for full problem description) a. The structure of 1,3-butadiene is usually written as H2C==CH--CH==CH2. The average bond lengths given are: C--C of 154pm and C==C of 133pm. Explain the fact that the observed value of the distance between the two central carbon atoms in 1,3-butadiene is 146pm. b. Which

DEET NMR

Why does DEET NMR show 2 triplets and 2 quartets at lower temperature 9C but 1 of each at higher temperature 80 C?

Short answer questions on human DNA, stearic acid, and aldaric acid

(See attached file for full problem description) D. Human DNA contains about 30% each of adenine and thymine and about 20% each of guanine and cytosine. The bacteria Clostridium perfringes contains about 37% adenine and thymine and 13% guanine and cytosine. Explain how this information relates to the structure of DNA in gene

Drawings of structures of amino acids

(See attached file for full problem descriptions) E. Draw the structure of the disaccharide cellubiose, This is two glucose monosaccharides with a beta-1,4' glucosidic linkage. Circle the anomeric carbon. Is this a reducing sugar? Explain. 2. See the attachment for the three amino acids Valine, Glutamic Acid, Histidine.

Acid Derivatives and Amide Properties

I need some help in answering these questions. Full explanations please! 1. The correct order of reactivity of acid derivatives towards nucleophilic attack is: esters > acid anhydrides > amides amides > esters > anhydrides carboxylates > esters > amides anhydrides > esters > amides 2. N-methylacetamide is an example of:

Identifying Organic Compounds

A colorless liquid A (C3H6O) was soluble in water and ether, and had a boiling point of 94-96 degrees Celsius. It decolorized a Br2-CH2Cl2 solution and gave a positive ceric nitrate test. On catalytic hydrogenation it formed Compound B (C3H8O), which did not decolorized the above bromine solution, but did give a positive ceric n

Determining Molecules from Spectral Diagrams

Compound S (C8H16) decolorizes a solution of bromine in carbon tetrachloride. The broadband proton-decoupled 13^C spectrum of S is given in Fig. 9.52. Propose a structure for S. I have attached the actual question from the book as it has Fig. 9.52 in it. There was minor blurring near the end of the chart so just for refere

Assorted State Change Questions

1 Describe the intermolecular force that must be overcome in converting each of the following from a liquid to a gas: A. Liquid O2 B. Mercury C. CH3I (methyl iodide) D. CH3CH2OH (ethanol) 2 Rank the following in order of increasing strength of intermolecular forces in the pure substances. Which do you think

Ceric Nitrate, Beyer, and Tollens Tests

I need some help in finding out what the compounds are from the scenarios: 1. A colorless liquid A (C3H6O) was soluble in water and ether, and had a boiling point of 94-96 degrees C. it decolorized a Br2-CH2Cl2 solution and gave a positive ceric nitrate test. On catalytic hydrogenation it formed Compound B (C3H8O), which

Chemical Differences Among Carbohydrates

1) How can you distinguish chemically between starch and three other carbohydrates (sucrose, glucose, & lactose)? 2) What would you expect to observe when adding one drop of iodine-potassium iodine reagent to each of the four carbohydrates? 3) How does Benedict's Reagent distinguish between carbohydrates? 4) When addi

Which of the following is an INCORRECT description of benzene?

Which of the following is an INCORRECT description of benzene? a. The CCC bond angles are all equal to 120 o b. The 6-membered ring contains alternating double and single carbon-carbon bonds c. The molecule may be drawn as resonance hybrid of 2 Kekule structures d. The molecule is planar Which of the followi

Problems Involving Dimethyl Ether

7.A. Dimethyl ether boils at 24 degrees Celsius whereas its isomer, ethanol boils at 78 degrees Celsius. Explain this fact. B. Make a sketch showing how dimethyl ether is able to solvate a cation such as K+. (See attached file for full problem description) C. Draw the structure of dimethyl ether, showing the 3-D shape at th

Chemical structures, hydrocarbons, and solubility

What is the structure for hexadecanol? What would explain why it is a solid rather than a liquid? How are ethanol, 1-octanol, propane-1,2,3-triol, and hexadecanol similar to their corresponding hydrocarbons (ethane, octane, propane, & hexadecane)? Do some of these alcohols possess more hydrocarbon character than other

Aromatic structures, and mass spec, molecular ion, realtive abundances

1.(refering to dexchlorpheniramine, pilocarpine, and 9-aminoacridine)--GO TO WWW.CHEMFINDER.COM TO LOOK UP STRUCTURES FOR THESE COMPOUNDS)-- For each ring in each structure, indicate if it is aromatic. Rationalize your decision for each ring (even those that are not aromatic). Make sure to indicate which (if any) lone pair el

Organic chemistry problems: Naming, Isomerism, pH

IUPAC name for CH3CH2CH2CH double bond CHCH2COOH Which exhibits geometric isomerism CH3C triple bond CH CH3CH2CH double bondCH2 CH3CH double bond CHCH3 Compound A has the molecular formula C8H14. Addition of bromine to A gives a new compound B, with the formula C8H14Br4. Treatment of A with and aqueous acid gave

Azo Dyes, Acid-Base Indicator and Ferrocene

1. What is the main structural feature of the azo dyes that causes them to be colored compounds? 2. Methyl Orange is an acid-base indicator. In dilute solution at pH greater than 4.4, it is yellow. At pH = 3.2 the solution appears red. Draw a structure of the species that is formed at the lower pH of the acid proton adds to t

Naming incorrect compounds with IUPAC

Each of the following names is an incorrect IUPAC name. Indicate, if possible, the correct name of the compound. Can you please explain why these names are not right? 1) 4-butyl 1-methyl 2-hexene 2) 2-ethylpentane 3)1-propyl 5-methyl benzene

Naming an IUPAC system

Name this by the IUPAC system H H / C=C / C-C C-C-C | Cl And this one: C-C-C-C-C | | F C-F

Stepwise mechanisms

Consider the reaction in attached document. What is a stepwise mechanism that accounts for both of the products shown. Please show me the mechanism. Show all intermediate structures and all electron flow with arrows. Also include resonance. In addition, what are the non-prefered products of electrophilic addition to the opposit

Acid catalyzed Fisher

Propose a detailed mechanism for the acid - catalyzed Fisher esterification of propanoic acid and ethanol. Show all resonance forms.

different resonance forms of two structures

Please see attached...I chose c The two structures shown are: a. constitutional isomers b. enantiomers c. different resonance forms of the same species. d. difference conformations of the same species. e. 5. diastereomers

Alkyl Halide Solvolysis

Choose the starting reagents: benzyl chloride and a solvent (water). Note the color of the solution. Return to the lab and place the flask on the stir plate. No other set up is required. You will monitor the reaction on the pull down TV and with TLC. Run a TLC sample before you start the reaction. Some reactants may not s

Organic Chemistry Bonding Properties

I need some help with these three questions on organic chemistry bonding: 13. Why it is important that any aldehyde used in Witting reaction be free of carboxylic acid impurities? 14. Explain why the C=C stretching mode gives rise to a rather weak IR band in 1-methylcyclohexane, while in its isomer, methylenecyclohexene,

What is the structure of the hydrocarbon?

A hydrocarbon was found to have a molecular weight of 80-85. A 10.02 mg sample took up 8.40 mL of H2 gas at 0 degrees C and 760 mm pressure. Ozonolysis yielded only two compounds shown in the attached .jpg. What is the structure of the hydrocarbon? See attached file for full problem description.

Calculate the degree of unsaturation in C4H6.

1. a. Calculate the degree of unsaturation in C4H6. b. Draw at least 4 iosmers with this formula (C4H6). 2. a. Explain why cis dichloroethene has a boiling point of 60 degrees C while trans - dichloroethen has a boiling point of 48 degrees C. b. Include drawings of the structures with dipoles in your answer.

Anti Addition

I need to paraphrase this "As a bromine molecule approaches perpendicular to the negatively charged pi cloud of the carbon-carbon double bond, its bonding electrons are repelled away from the bromine atom nearer the double bond, leaving it with a partial positive charge. As the positively charged bromine penetrates the pi cloud,