Mass Fragmentation Patterns for a Few Compounds

See the attachments. Guideline 1. The relative intensity of the molecular ion peak is greatest fro the straight chain compound and decreases as the degree of branching increase. 2. The relative intensity of the molecular ion peak usually decreases with increasing molecular weight in a homolo...

Synthesis Problems of Alcohols

Please show the steps needed in order to synthesize the finished product from the starting material. 1. Suggest a synthetic route to each of the following alkenes using an alcohol. Keep in mind that acid-catalyzed dehydration often gives mixtures of products due to arrangement. (See attachment fo...

One exception in organic nomenclature

The priority of amine is higher than alkene still the compound above uses hexene as suffix name? What are then priority used for? And how does one determine the rank of the suffix ending? Do you have a general table or explanation? (see attached table)

Rate of Electrophilic Substitution

Why is halogenation the fastest one? Why is friedel crafts reactions the slowest? And why is it so slow that it can not undergo meta substitution electrophilic reactions?

Major Concerns with HPLC

In HPLC, how often should I need to run standard with samples? Why? If the retention time is changed with real samples compared to standard, how can I determine if the peak with changed retention time is samples are actually compounds A and B?

Calculating amount of caffeine from absorbance

The samples 75mL of coffee (Sample A) and tea (Sample B) were run. Determine the amount of caffeine/mL in a cup of tea or coffee and then the total amount of caffeine in a cup of 200mL. Are there difference between the values at the two different wavelengths and why might this be the case? Explain ...

Column Chromatogrpahy vs HPLC

What types of stationary phases used for column chromatography and HPLC? How these staionary phase work and what types of compounds can be separated using this? What are the difference in the stationary phases used for column chromatography and HPLC? Why are they difference and why do not use the ma...

Assorted questions on aromatics and grignards

1. Give the structures of all possible products when 3-bromopentane reacts by the E2 mechanism. 2. Ethers and alcohols can be isomeric. Write the structures, and give names for all possible isomers with the molecular formula C4H10O. 3. Using a Grignard reagent and the appropriate aldehyde o...

Assorted Alkene Reactions

Hi. I'd like to check answers to some things before my final. I like handwritten work because it really helps me with the thought processes, like taking a test. 1. Write an equation for the sequential hydroboration and H2O2/OH ̄ oxidation of 4-ethyl-3- heptene. 2. Indicate the main monos...

Enantiometrically Pure Retrosynthesis

There are many ways of making (R)3-ethyl-4-methylpent-1-yne. Explain what enantiomerically pure retrosynthesis is and show the enantiometrically pure retrosynthesis of this alkyne via a substitution mechanism.

Goals of Recrystallization Procedures

The goal of the recrystallization procedure is to obtain purified material with a maximum recovery. For each of the following situations, explain why this goal would be adversely affected. a) In the solution step, an unnecessarily large volume of solvent is used. b) The crystals obtained after ...

Synthesis Questions: Stability and Reactivity

Can you please explain these problems. See the attached file. 1.) Which form of molecule A is the most stable (1, 2, or 3)? Provide a graphical (i.e. figures not graphs) provide an explanation for your answer. 2.) Enamines are generally reactive toward electrophiles. For example, compound E re...

Nomenclature of alkanes and alkenes

This solution describes how to name alkanes and alkenes according to the rules of scientific nomenclature. It was originally part of my ebook EVERYTHING YOU NEED TO KNOW ABOUT CHEMICAL NOMENCLATURE. If you want more information or a more complete description to include inorganic compounds, please se...

Fluorescence Chemistry lab

Chemistry 3211 Experiment #5 The Simultaneous Determination of Chloride and Bromide Ions Using Fluorescence Quenching 18 June 2013 ABSTRACT The fluorescence quenching method was used to analyze an unknown sample using fluorescent indicators quinine and acrdine to...

Enamine Synthesis Mechanism

(a) (i) Provide a retrosynthetic analysis of the enamine below in order to identify the starting ketone and amine. Please see the attached document for the diagram. (ii) Write a reaction mechanism to explain the formation of the enamine under acidic reaction conditions from the ketone and pyr...

Sigmatropic rearrangements

(a) The pericyclic reaction shown below is an example of the Cope rearrangement. (i) Classify the sigmatropic rearrangement as an [n,n]-sigmatropic rearrangement, where n is an integer. Show how the classification is arrived at as part of your answer. Please see the attached document for the...

Rate of Initiated Radical Polymerization

What are the basic steps of initiated radical polymerization? Derive the rate expression of initiated radical polymerization, clearly stating the assumptions. How does this rate depend on the monomer and initiator concentrations?

Kinetic Molecular Theory: Benzoic Acid

Benzoic acid, C6H5COOH, melts at 122 degrees C. The density in the liquid state at 130 degrees C is 1.08 g/cm^3. The density of solid benzoic acid at 15 degrees C is 1.266 g/cm^3. In which state is the average distance between molecules the greatest? Explain the difference in densities at the t...

Dimerization of C5H6

Suggest a method for measuring the rate of the following reactions: i) 2H2O2(aq) ------> 2H2O (l) + O2(g) ii) HBr(g) -----------> H2(g) + Br2(g) (colorless)............(colorless)....(dark red-brown) For the dimerization reaction 2C5H6(g) --------> C10H12(g) Change in the con...

Changes in Solid and Liquid States

Matter exists in three different states: solid, liquid, and gas. Depending upon its physical properties, matter will be found in one of these states at ambient temperature and pressure. Describe a situation where a substance changed between the solid and liquid states or between liquid and gas s...

Chlorination Reaction

4. For the reactions: Cl + H-CH3 --> Cl-CH3 + H Cl + H-CH3 --> CH3 + H-Cl a) Calculate the change in H for each reaction using bonds dissociation enthalpies. b) One of these reactions is the rate-determining step in the correct mechanism for the chlorination of methane. Wha...

Electrophile and leaving group

Please see the attached questions with a few parts concerning electrophiles and leaving groups. I am a little confused on how to proceed. An explanation with work would be really nice. Thanks for the help.

Liquifying Propane

Please show all work for the final calculations and answers. Thanks! 1) Calculate the entropy change that occurs when 3.5 moles of an ideal gas expands from 1.75 L at 20 degress Celsius to 8.46 L at .54 atm. Explain your strategy for solving this before you start. 2) Pop is packaged under CO...

Empirical and Molecular Formulae

The analysis of an organic compound produces the following elemental analysis: % C is 59.999% and % H is 4.476%. What are the empirical and molecular formulae for this compound? The estimate for the molecular weight of the compound is between 175 and 185 g/mol.

Organic vs. Silicon-Based Solar Cells

Compare and contrast organic and present day silicon-based (inorganic) solar cells. Describe the physics behind the operation of these solar photovoltaic devices and then discuss how their efficiencies are determined. What advantages and disadvantages exist for both organic and inorganic sol...

Bomb and Radiation

Consider a van parked in a lot outside a professional football stadium in Atlanta, GA on a Sunday afternoon. One ounce of radioactive isotope Cesium 137 was mixed in with the explosive that has been detonated and has caused considerable blast damage. The dust cloud carries toward the nearby downtown...

Fisher Projection Question

Draw the Fisher projection formulas for the following: a. L-ribose b. L-arabinose c. L-glucose d. L-talose Draw the Fisher projection formulas for the following and then convert them to three-dimensional representations: a. L-threose b. L-erythrose

Determining Optically Active Forms

Which of the following substances can exist in an optically active form? a. 1,3-dibromopropane b. ethyl cyclohexane c. 3-ethylpentane Please refer to the attachment for full problem set.