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    Organic Chemistry

    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).

    Solvent for Industrial Processes

    A solvent for an industrial process requires the use of phenol or benzene. Both are about the same in effectiveness for the process, and of course, gloves will be used when handling either solvent. As an environmental safety officer for the company, which one would you recommend the use of and why? Also what set-up would you rec

    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

    18-O and 16-O Isotope Effects in Infrared Spectroscopy

    The Pt compound below shows an infrared band at 822 cm-1 that has been attributed to the O-O stretching mode. This is the mode where the O atoms move away from each other and the Pt-O stretching is not significant. If you approximate the O-O unit as a harmonic oscillator, where would you expect the 18-O compound to absorb? K

    Fractional Distillation and Reflux Ratios

    What is the significance of reflux ratio in fractional distillation? Also what exactly does the formula, Ya/Yb = Pa/Pb = PaNa/PbNb, mean in terms of fractional distillation?

    13C NMR and 1H NMR Equivalency of Carbons and Protons

    Please see the attached file for the complete problems. 1. For the compound below tell how many signals you would expect the molecule to have in its normal, broadband decoupled 13C NMR spectra. 2. Identify the indicated sets of protons as unrelated, homotopic, enantiotopic, or diastereotopic. 3. For the compounds below

    the solubility of silver phosphate in pure water and Na3PO4

    Silver Phosphate, Ag3PO4, is an ionic compound with a solubility product constant Ksp of 206 x 10 ^ - 18. Calculate the solubility of this compound in: a) pure water b) 0.2 mol L-1 or 0.2 M Na3PO4 I was able to solve part a, I got the solubility of silver phosphate in water to be 1.76 x 10 ^ -5 M. I am not sure how

    Measuring Concentration of Acetic Acid and Other Organic Acids

    If I have an unknown aqueous solution that exhibits a pH of approximately 4.0 but is known to consist of predominantly organic acids such as acetic acid, formic acid, benzoic acid, pyruvic acid, phenolic acid etc. etc. What analytical method would be employed to measure and determine the concentration of each acid in solution

    Organic Chemistry and NMR

    Tell how the attached NMR, MS data and Infrared spectroscopy support that my unknown liquid is ehtyl acetate. See attached file for full problem description.

    Density and Identity of Carbon Tetrachloride

    1. The mass of 5.00 mL carbon tetrachloride is 7.97g. What is the density of the carbon tetrachloride? 2. An unknown liquid is found to be insoluable in water, has a density of 0.73g/mL and a boiling point of 35degrees C. The most likely identity of the liquid is____?

    Atomic Absorption

    See attached file for full problem description. Analyze the data from McDonald Creek Site # 3 and 4.

    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

    Calculate the molar mass of sucrose. How many mol sucrose did you start with in this lab? How many mol ethanol would you obtain if all the sucrose is converted? I used 25g sucrose in 150 ml.

    Energy Eigenfunctions of a Particle

    Find <px2> for the first three energy eigenfunctions of a particle in an infinite dimensional well. (Hint: You might want to use the energy eigenvalues to avoid a lot of detailed calculations.)

    Geometry and isomerism in Organic Chemistry

    Isomers/VSEPR Questions. 1. Diethyl ether and butanol are .............. isomers. 2. A non zero dipole moment is exhibited by............. 3. The bond angle in PH3 is............ 4. ......... has trigonal planar shape. See attached file for full problem description.

    Preparing Given Compounds

    Working on my lab practical and I need to prepare the following compounds. Could you please help me with them. See attached file for full problem description.

    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

    Crystallization of Sulfanilamide

    We are performing an experiment involving the crystallization of sulfanilamide using 95% ethyl alcohol as the solvent. I am having trouble creating a hypothesis and I wanted your help on creating one. The graph attached on the scan will help.

    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).

    Using the Hückel rule for aromaticity

    On the basis of the Hückel rule for aromaticity, decide whether each of the attached compounds is aromatic or not, and state why. Note: If you have the correct answer but the wrong reason, you will get no credit.

    Organic Chemistry and E and Z

    2. Develop a four point argument to predict whether O or N is thermodynamically more basic in the following structure (See attachment for structural formula) 3. Predict whether the E or Z will be produced by E2 elimination for the following structure (1-bromo-1,2 -diphenylpropane). Use wedge and dashed line of Newman or sawho

    Matching Structures to Descriptions

    See the attached file. 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 peptid

    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