What is the initial boiling point of this liquid mixture? What is the composition of the vapor in equilibrium with the initial liquid? What is the composition of the initial condensate?

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Pre-Lab Questions for Integrated Alkene-Distillation Lab – Part 1

In this lab you will separate a mixture of organic liquids by one of two methods: simple or fractional distillation. Your partner group will do the alternate method. In theory, which method should give the better separation? Briefly explain why.

A mixture of 10 mL of isoamyl acetate (MW=130.2 g/mol and density=0.88 g/mL) and 15 mL of methyl benzoate (MW=136.2 g/mol and density=1.09 g/mL) is distilled. Calculate the mole percent for each component.

Use the mole %’s from question 2 and the figure below to answer the following questions.

  1. What is the initial boiling point of this liquid mixture?
  2. What is the composition of the vapor in equilibrium with the initial liquid?
  3. What is the composition of the initial condensate (the condensate which forms from condensation of the vapor in equilibrium with the initial liquid)?
  • The distillation curves, one simple and one fractional, from a mixture of liquids is shown below.
  • a) Which curve, solid or dashed line, is the simple distillation? Which is fractional? How could you distinguish between them?
  • b) The possible liquids being distilled are in the table below. What are the actual identities of the two liquids?

Liquid Boiling point (degrees C)

2-methyl propane 27.8

butane 30.2

pentane 36.1

hexane 69

cyclohexane 80.8

 

Draw all of the substitution and elimination products formed when the alkyl halide below is treated with a) CH3OH and b) KOH. Indicate stereochemistry of products, as well as mechanisms of formation

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Organic Chemistry II

Problem Set H- Elimination Reactions

Instructions: Complete all problems prior to the deadline. Upload to the Problem Set H assignment on Canvas. After the key posts, correct your problem set, and upload your corrections as a second upload to the Problem Set H assignment.

Part 1: Smith Problems

Problems from “Organic Chemistry” 6 ed by Janice Smith.

  1. Draw the structures of two different alkyl halides that yield the alkene as the only product.

Alkyl Halide 1

Alkyl Halide 2

  1. Draw all constitutional isomers formed in each elimination reaction. Label the mechanism as E1 or E2.

E1 or

E2?

  1. Taking into account stereochemistry, predict the major E2 product formed. Show why.
  2. Draw the structure, including stereochemistry, of an alkyl chloride that forms each alkene as the exclusive E2 product.
  3. Draw the product(s) formed when treated with excess NaNH2
  4. Draw the structure of a dihalide that could be used to prepare the alkene. There may be more than one possible.
  5. Draw all of the substitution and elimination products formed when the alkyl halide below is treated with a) CH3OH and b) KOH. Indicate stereochemistry of products, as well as mechanisms of formation.
  6. The following reactions do not afford the major product that is given. Explain why and draw the structure of the major product actually formed.
  7. Draw a detailed, stepwise mechanism for each reaction.
  8. Draw a detailed, stepwise mechanism that illustrates how four organic products are formed in the following reaction:

Product 1:

Product 2:

Product 3:

Product 4:

  1. Draw all products formed by treatment of the dibromide (B) with one equivalentof NaNH2. Label pairs of diastereomers and constitutional isomers

 

Which gaseous chemical has been studied? What is the effect of this chemical on the studied protein or enzyme? Which impact/effect does this or might this effect have on the biological function of this particular protein or enzyme?

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DISCUSSION QUESTION

Discussion 1: Contemporary Biochemistry-Related Topics

In this discussion board (DB), please post a thread and share:

  1. From recent news, video, or media, select a biochemistry-related topic that interests you. Write the topic as your header for your original post.
  2. Answer the following questions in your original discussion thread:
    (1) Your impression of the information from the news article/video/or media?
    (2) What questions in your topic/concern still need to be explored?
    (3) How did the information use the scientific method?
  3. Include a credible resource to have your classmates explore this topic. APA format.

Discussion 2: Topic: Protein function and gases

As you learned about the importance of three-dimensional structure (conformation) and protein function and about the role of enzymes in many cellular processes, ranging from metabolism to regulation, and you further learned that the 3D structure of proteins and enzymes can be modified and altered by many chemicals, both, endogenous or through external exposure.

In this discussion, do some research (preferably on NCBI PubMed) and look for recent scientific articles showing the impact of gases (e.g. nitric oxide, superoxide anion radicals, or hydrogen sulfide) on proteins or enzymes critical for normal cell functioning. Select ONE article of your interest and start a discussion.

As you work on this assignment address and discuss the following:

  1. Which gaseous chemical has been studied?
  2. What is the effect of this chemical on the studied protein or enzyme?
  3. Which impact/effect does this or might this effect have on the biological function of this particular protein or enzyme?

Be sure to include the reference of your selected article at the end of your initial posting to receive full credit. These posts need to be a couple of paragraphs and should not exceed a page (minimum of 250 words required for a full credit of original post). You must write at least 250 words on one page and include details in your original discussion post.

 

What are the symmetry elements? Do they have a center of symmetry? Are they abelian?

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Quick question about crystallography

For point groups 422 and 4mm

  1. what are the symmetry elements?
  2. Do they have a center of symmetry?
  3. Are they abelian?

 

Give the chemical equation involved in the reaction on the video. Find another link on the website for amide. Give 2 uses of amines and amides.

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Assignment

 Alkanes

Link to the website:

Questions:

  1. Physical Property of alkanes:

a.1  color: no color

  1. Note the color of flame produced in the video.: Blue
  2. Give and write the chemical equation of the following chemical reaction of alkanes.

c.1   Combustion

c.2   Cracking

 

Alkenes

Question:

  1. Physical Property of alkenes:

a.1  color

  1. What is the reaction of alkenes with potassium permanganate and bromine water?

 

Alkynes

Question:

  1. Physical Property of alkynes:

a.1  color

  1. What is the reaction of alkynes with potassium permanganate and bromine water?

 

Aromatic hydrocarbons

Link to the website:

Question:

  1. Physical Property of benzene:

a.1  color

  1. What is the reaction of benzene with potassium permanganate and bromine water?
  2. Write the equation involved to produce nitrobenzene.

Preparation of alcohol

Link to the website:

 

Properties of alcohol:

Link to the website:

Questions:

  1. Give at least 4 uses of ethyl alcohol.
  2. What is the role of yeast in the fermentation process?
  3. Is ethyl alcohol soluble in water? CHCl3? CCl4? Rationalize each answer.

 

  1. Find a website for the following:
    1. Preparation of Carboxylic acid ( Benzoic acid )
  2. Physical Properties of Carboxylic acid
  3. Chemical Properties of Carboxylic acid
  4. What are the derivatives of acids? Give example.
  5. Give the equations involved in esterification of an acid. Find any website to support your answer.

Compare formic acid with acetic acid and oxalic acid.

Properties of Amine

Link to the website:

Questions:

  1. Give the chemical equation involved in the reaction on the video.
  2. Find another link on the website for amide.
  3. Give 2 uses of amines and amides.

 

 

What type of tissue is the student observing? Where might this tissue be found in the body?

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Organic Chemistry

Discussion Question #1: During a microscopy exercise in the anatomy laboratory, a student makes the following observations about a tissue section: A) the section contains some different types of scattered protein fibers–that is, they exhibit different widths (some are branched and some are long and unbranched); B) the observed section has some “open spaces”–that is, places between both cells and the fibers that appear clear with no recognizable features; and C) several connective tissue cell types are scattered throughout the section, but these cells are not grouped tightly together.

What type of tissue is the student observing? Where might this tissue be found in the body?

 

Write an 800-word essay explaining the five main branches of chemistry.

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Branches of chemistry

Write an 800-word essay explaining the five main branches of chemistry.

1. Organic Chemistry
2. Inorganic Chemistry
3. Analytical Chemistry
4. Physical Chemistry
5. Biochemistry

Discuss your data in terms of the effect that the mutation may have had on activity. Discuss types of inhibition and differences of Ki between the different inhibitors.

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Experimental Procedures, Results and Discussion

Writing Assignment:

Write an Experimental Procedures, Results, and Discussion sections for labs 6 and 7 in the format of Journal of Biological Chemistry (JBC). This should include details such that an experienced biochemist could reproduce the experiments from the kinetics and inhibition experiments you performed. Also, be sure to discuss the data as though you’re convincing someone of the significance of what you’ve done.  Treat this as novel research that you want to publish. Like before, find a JBC article that includes enzyme kinetics and/or enzyme inhibition to help guide you. Be sure to include either the printed article or cite the article with your report.  In addition, I want you to include a Supporting Information section where you will show sample calculations from your report. This will be less formal and can be in any format you like as long as if it is clearly labeled and easy to read (typed or written).

What should be included in the paper?

Experimental Procedures:

  •         All details for performing the experiments performed in Lab 6 and 7 (enzyme kinetics and inhibition, respectively)

Results: (make sure to label all figures, graphs, and tables as seen in publication)

  •         From Lab 6

o   Prepare a figure with your graphs from the experiment.

  • Graph 1: Michaelis plot for the WT and mutant enzyme.
  • Graph 2: Lineweaver-Burk plot for the WT and mutant enzyme

o   Table showing x-intercept from Lineweaver-Burk, y-intercept from Lineweaver-Burk, KM, Vmax, and turnover number for both enzymes. (see table example below)

  wild-type mutant (                 )
x-intercept from LB    
y-intercept from LB    
KM    
Vmax    
Turnover (kcat)    

 

  •  From Lab 7

o   Michaelis-Menton graphs for sodium phosphate and L-phenylalanine inhibition (separate graph for each, new line for each concentration)

o   Lineweaver-Burk for sodium phosphate and L-phenylalanine inhibition (separate graph for each, new line for each concentration).

o   Table showing Km, Vmax, turnover and Ki for all samples tested (see table example below)

 

  uninhibited 100 µM NaPO4 500 µM NaPO4 1 mM L-Phe 5 mM L-Phe
KM          
Vmax          
Turnover          
Ki          

 

 

Discussion: (this is not a limited list- be sure to discuss all the important findings of your experiments)

  •         Discuss your data in terms of the effect that the mutation may have had on activity
  •         Discuss types of inhibition and differences of Ki between the different inhibitors. For example:

o   Based on your data and your knowledge of the enzyme, what kind of inhibitor is NaPO4?

o   Based on your data and your knowledge of the enzyme, what kind of inhibitor is L-phenylalanine?

 

 

Supporting Information:

In addition, please show a sample calculation for the following:

o   Conversion of the initial rate in absorbance/second to concentration/second.

o   KM­

o   Vmax

o   Turnover

o   Ki

Why is the difference between a physical or chemical change?

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Why is the difference between a physical or chemical change?

 

Given for an unknown compound are MS and IR spectra. Determine the structure of the compound, provide a fragmentation reaction—meaning mechanism–from the molecular ion giving the base peak, and identify two bands in the IR consistent with your proposed structure.

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Identify fragment patterns and IR peaks of the following structure.

Relative Intensity

100 –

80 –

60 –

40 –

MS-Itd-9540

20 –

0

I II 11111 I I dhirlI 11111 CI 7n 40 o

II ‘i 120 140 160 rn/z

II I 1 11 1 11 11 1 11 I 180 LULl

  1. Given for an unknown compound are MS and IR spectra. You are to determine the structure of the compound, provide a fragmentation reaction—meaning mechanism–from the molecular ion giving the base peak, and identify two bands (give frequencies and functional group) in the IR consistent with your proposed structure

Relative Intensity

100-

80-

60-

40-

20-

foo

MS-I0-9540