List three balanced chemical equations that include your element, include all states of matter.

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Please answer each question. Selenium

1. Discuss the following Periodic Trends for the element’s group: Zeff, Atomic Radius, Ionization Energy,
2. Give names and chemical formulas for five compounds in which this element exists. For these compounds, list the molar mass, the percent composition of each element, classify as ionic or covalent, and draw the Lewis Dot structure.
3. List three balanced chemical equations that include your element, include all states of matter.
a. Describe why the reaction is significant? What are the uses of the products of the reaction?
b. For one of the reactions, write your own stoichiometry problem and solve it.
4. What is the specific heat of your element in its most stable state at room temperature? Calculate the energy required to heat 25.0 g of the element from 0oC to 50oC (remember to account for ΔHvap or ΔHfus if there is a phase change).

Perform a direct titration of an unknown diprotic acid with a strong base in order to identify and determine the molecular weight of an unknown acid.

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Title : Acid-base Titration of a Diprotic acid and back titration of Unknow

Abstract:

The purpose of this laboratory experiment was to perform a direct titration of an unknown diprotic acid with a strong base in order to identify and determine the molecular weight of an unknown acid. Back titration of an unknown compound was performed to determine the weight percent of CaCO3 . The molecular weight of a diprotic acid was …… g/mol and it was identified as …… acid ; Also the weight percent of CaCO3 was calculated to be …… % +/- ……. .

Introduction:

The major aspect of acid-base equilibrium was used during this experiment ; The main laboratory technique that was done during this lab is acid-base titration in which a strong base (NaOH) was titrated with a strong acid (HCl) . Two titration methods were used which are direct and back respectively . Originally an unknown diprotic acid (#839) is provided and certain amount of it was diluted and titrated directly with a strong base NaOH ( 0.0214M +/-0.0002) .Calibrated pH electrode was used during the titration procedure to measure the solution’ s associated pH , therefore creating a titration curve. The unknown diprotic acid deprotonates twice with two equivalence points and  acid dissociation values ( ka1 , ka2 ) . In order to determine the largest incremental change in pH change by volume , the derivative of the titration curve was used. The equivalence point represents the moles of used NaOH at equivalence point can be traced through stoichiometric relation and basic molecular mass calculation to identify the provided unknown diprotic acid .

H2A (aq)  < – – – — – > H+(aq) + HA–(aq)              ka1

HA– (aq) < – – – – -> H+(aq)  + A2-(aq)                          ka2

The second part of this laboratory experiment involves the back titration of an unknown mixture (3-3) with strong base NaOH (0.0214M +/-0.0002) to determine the weight percent of present CaCO3 .During direct titration the volume of titrant and the associated pH are used to find the two ka values. However ,by using stoichiometry the molecular formula of diprotic acid is identified and therefore concentration and molecular weight were calculated. The back titration happens only in presence of excess base added to an analyte which is CaCO3 ; therefore an excess titrant can help to determine the concentration of an analyte. Back titration is useful in finding out the concentration of an insoluble diprotic acid salts such as CaCO3  .

CaCO3(aq) < – – – – > Ca2+(aq) + CO3(aq)2.      Ksp = 2.7 x 10 ^ -33      pH= 7.00   25C

Experimental:

This experiment is divided into three parts which are direct titration of an unknown diprotic acid, back titration of an unknown compound and clean up . The equipment used in this laboratory experiment include 50mL burette, 100mL volumetric flask, spatula , small weighting boat , calibrated pH meter , 25 mL pipette , watch glass and heating plate . The used materials were 0.02+/- 0.0001 M NaOH, 0.1052+/- 0.0002M HCl , diprotic sample , unknown sample and buffer solutions at pH 4 and 7 .

The preparation of an unknown diprotic acid sample (#839) was done by weighting around 0.12g +/- 10% and diluting it to 100 mL volumetric flask using distilled water. Next. , 25 mL of diluted diprotic acid solution was pipetted using 25 mL pipette and transferred to another 100mL beaker and placed on the magnetic stirrer. A magnetic bar was pulled into the beaker ; also , pH meter was placed into the beaker in a way that it was not touching the stir bar and the burette. Burette filled with twice with NaOH solution and direct titration started. The first equivalent point happened around pH of 4 and the next pH equivalent point was determined quantitively. Once both pH values of equivalence point were determined , the titration could have be repeated once more it was necessary.

The back titration was done on an unknown compound number 3-3, 0.2g +/- 10% was quantitively transferred to 100 mL beaker along with approximately 10 mL of distilled water . 25 mL of HCl ( 0.1052M +/- 0.0002 ) was pipetted into the beaker and the beaker was sealed with watch glass and  placed on hot plate for around 10 minutes in order to boil. After the allocated time , the beaker removed from hot plate and left on fume hood to adjust its temperature to the lab area temperature. The beaker’s content was transferred into 100mL volumetric flask using funnel and diluted to the mark using distilled water. After , 25 mL of the dilution was pipetted into a 100mL beaker and placed on the magnetic stirrer. Like the last part pH meter and burette were adjusted toward the beaker and titration started . pH was recorded by adding every 0.5-1 mL of NaOH into the beaker . The increments of titrant would become even smaller as rapid pH was detected. The process was done until the time that both equivalence points were observed.

After finishing both titrations , all waste solutions were poured into waste sink and all glass equipment were washed with soap and tap water and then rinsed with distilled water . Magnetic stir bar and unknowns were handed back to TA and electronic equipment (pH meter ) was plugged off and wrapped properly .

Results :

How do you counsel a patient about it, how do you decide on a dosage

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this is my feedback
(Your draft is a good start, but my main issues are the use of inappropriate references, such as drugbank, chemicalbook, ‘prednisolone’. There seems to be an over-reliance on websites for chemical data – please use an appropriate medicinal chemistry textbook, such as “An introduction to medicinal chemistry by Graham L Patrick” and for pharmacology I would recommend “Rang and Dale’s Pharmacology”.
Secondly, some of the data, particularly in your pharmacokinetics section, appears to be from a reference with details METHYLprednisolone. This is not the correct drug – this represents a major issue in your draft.
Finally, I think that your pharmacodynamics/mode of action sections need revision. You have tried to combine too many concepts into these sections and as such, none are covered in sufficient detail or with clarity. Please focus on the action of prednisolone as a corticosteroid and its action on the glucocorticoid receptor.)

fix all the errors
this the essay
write a 1000 word report on this medicine This needs to include the following points -The chemical structure of the medicine with the functional groups identified -The mode of action of the medicine – i.e. the pharmacology surrounding its action – The pharmacodynamics (what the medicine does to the body) and the pharmacokinetics (what the body does to the medicine) of the medicine including how it is metabolised and excreted by the body, what the half life is etc. – How the medicine is used in practice, which patients are treated with it, what are its main 5 side effects, how do you counsel a patient about it, how do you decide on a dosage. – table about medicine interaction -diagram medicine harmfulness -references from books (easy to access online) use BNF/ articles PLEASE FOLLOW THE MARKING SCHEME THAT IVE ATTACHED

What are the kinetic parameters? KM, kcat, specific activity, pH optimum, etc., and for what substrates?

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Hi! I am attaching the details of the paper. I need you to write a research paper in the Enzyme: Pyruvate decarboxylase with at least two peer-reviewed articles.

And it should have at least one primary article from an American chemical society publication.
All the instructions to follow it is in the attached file. Image will not be counted as part of the page requirement as per instructed.

A thorough and complete paper will include the following:
 What organism(s) utilize the biomolecule? Is it homologous to enzymes in other organisms?

 A discussion of the structure and function of the biomolecule.
 How does it catalyze the reaction? Acid-base catalysis? Cleavage of carbon-carbon bond? Oxidation? Something different? There are hundreds of reaction types; describe the reaction.

 What cofactors, if any, does it require?

 What are the substrates and end products?

 Are there any known inhibitors? If so, how do they inhibit the reaction?

 If a 3-D structure is known, include an image and discussion of the structure. ( image do not count toward the page requirements )
 What are the kinetic parameters? KM, kcat, specific activity, pH optimum, etc., and for what substrates?

more details of paper is attached. Thank you.

Write clear, concise, scientific laboratory reports using American Chemical Society style for each experiment. 

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Estimation of Aspirin – A Simulated Lab – Amrita Labs

Objectives

After completing this lab activity, you should be able to,

  1. Estimate the amount of aspirin in a solution.
  2. Synthesize aspirin and explain the mechanism.
  3. Use Material Safety Data Sheets (MSDS) to obtain information such as molecular formula, physical properties, hazards, and disposal procedures for chemicals used in each experiment.
  4. Prepare and maintain a laboratory notebook, including a write-up of each experiment that details the purpose, chemical equations, calculation of theoretical yield, percent yield, and record of experimental observations.
  5. Write clear, concise, scientific laboratory reports using American Chemical Society style for each experiment.
  6. Use critical analysis skills to interpret data and draw conclusions.

DETAILED INSTRUCTIONS FOR LAB ACTIVITY COMPLETION:

This is your lab activity for the course chapter twenty-four (24).

Therefore, the first step is to visit the following webpage: http://vlab.amrita.edu/index.php

Once you have reached this webpage, register with a username and password. This is a free registration.

After you have registered, log in and copy and paste the following link into your browser:

 

The purpose of this page and subsequent pages is to provide you with the resources to complete this lab activity.

After reading the theory page, click on procedure. This page explains how to conduct the laboratory experiment online. This page also provides you with guidance on important points to remember, if you do this experiment in actual settings in a lab.

Then, complete the self-evaluation. This is for your own reflection. After, reflection, click on animation and conduct the experiment and complete the given assignment. You can also use the given reference page for more information.

After you conduct the experiment and complete the assignment questions, you need to submit only the lab report. In the lab report, you include your lab simulation results. The report should be written as if you conduced the experiment (simulated) to find out the answers according to the experiment. After completing the report, please upload the report as a .doc file.

The lab report has to be written following the ACS guidelines. Therefore, please use the following link to understand what subtitles should be included in the lab report.

At the end of the laboratory report, please include a section covering the information derived from the Material Safety Data Sheets (MSDS) relevant to the chemicals you come across in this experiment. You can get this information by visiting the following website:

Find 4 new things that you never knew about these topics, and talk about it in a well referenced, well written paper.

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Write a 3-page paper on this topic,Find 4 new things that you never knew about these topics, and talk about it in a well referenced, well written paper.

Discuss “Condensation Reactions” giving at least two examples.

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Discuss “Condensation Reactions” giving at least two examples. Your explanation should include relevant mechanisms and references to actual uses in life. Use graphics and pictures from online sources to support explanation. Attached files and MUST be used as two sources.

Choose a molecule used in healthcare, industry, or found in a natural source and discuss the importance of this molecule.

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First, choose a molecule used in healthcare, industry, or found in a natural source and discuss the importance of this molecule. Be sure to include at least one outside source and make sure to follow APA citation guidelines.

In the second , we will be practicing naming ionic and covalent compounds as well as polyatomic ions. To begin, give the chemical formula for each of the following: A covalent compound containing no more than two types of elements, an ionic compound no more than two types of elements, and an ionic compound containing a polyatomic. Be sure that these compounds are valid (for example, the charges balance out in the ionic compound) and that the subscripts do not exceed 10.

What would be a pharmacological intervention that could have helped her and other patients with a similar condition?

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Retell the tragic story of Libby Zion from the *psychopharmacology* point of view (10 pts). Discuss her symptoms, diagnosis (2), focus on drug mechanisms and interactions (2), argue both for and against the role of cocaine in pharmacological mechanisms, causing her death (4). What would be a pharmacological intervention that could have helped her and other patients with a similar condition? (2).
-Please be sure to focus on pharmacology and drug interactions rather than just psychological symptoms as well. This will require you to utilize outside sources.

Write an essay in which you describe in a clear and organized way the important properties, reactions, and most common uses of your assigned element.

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Assignment Goals: In this assignment you will

:Research the scientific and popular literature to identify chemical and physical properties of the element you have been assigned.

Write an essay in which you describe in a clear and organized way the important properties, reactions, and most common uses of your assigned element.

Utilize the assignment feature in blackboard to submit your essay.

Peer review two essays. Source Material:This assignment is a research project. You will conduct your own research using computer resources as well as print resources. You are strongly encouraged to consult with one of the reference librarians to assist you in locating appropriate library resources. Examples of printed compendia: CRC Handbook of Chemistry and PhysicsThe Merck IndexWebsites that might be particularly useful:NIST Chemistry WebBook: URL -http://webbook.nist.gov/chemistry/WebElements Online Periodic Table: URL -http://www.webelements.comMount Aloysius Library: URL -http://www.sciencemag.org/feature/contribinfo/prep/res/refs.shtml.Student Instructions:The paper that you will be writing is an Analytical Paper. The staff at SUNY Empire State College Writer’s Complex explain the analytical paper as: “To analyze means to break a topic or concept down into its parts in order to inspect and understand it, and to restructure those parts in a way that makes sense to you. In an analytical research paper, you do research to become an expert on a topic so that you canrestructure and present the parts of the topic from your own perspective.”Mechanics:Your essay must not exceed 1000 words. You will lose points if the essay is greater than 1000 words or less than 900 words. The essay should have an introduction, a logical development, and a conclusion. . A complete list of the references that you used should be given at the end. The references are not part of your 1000 word limit. You are expected to write in a scientific style. The essay should be written for an audience that are not scientists, but you should assume that the reader is intelligent but lacking topic-specific knowledge.All factual data and professional opinions must be referenced in the body of the text. Citations should be limited to a number, (do not use author and year). This number should be related back to the complete list of references. One number should be given to each reference. See http://www.sciencemag.org/feature/contribinfo/prep/res/refs.shtml. The purpose of the list of citations is so that the reader can find reference sources unambiguously. For internet sources, give the complete URL, the name of the page, and name of the author or compiler and the date last updated.During the course of your research you will rely on, but not be limited to, Source Material from the library, textbook, and relevant web sites. Because each student has a different element the resource materials that a student chooses to utilize will vary. Therefore,keep in mind that each element has unique answers to theGuiding Questions because each element has unique characteristics.Guiding Questions:In two or more paragraphs, not a list, related the following information. Group the information into sensible paragraphs each with a topic sentence that previews the type of information to be discussed.

1.Give the name and symbol of the element with atomic number and mass number. Tell the number of protons, neutrons, and electrons.

2.Tell the date the element was discovered, where, and by whom (if known). If the element was discovered in antiquity, tell which nation or tribe was the first known to use the element.

3.Tell how or why the element got its name.

4.Give the following data about the element:

melting point and boiling point

density

most common ionic charge

phase at room temperature

5.Describe the appearance of the element. Include information on

color

what it feels like

degree of hardness or softness (you may use the Mohs scale, but also describe qualitatively
6.Tell about the sources of the element. Include

where in the world it can be found,

in what form it is found (liquid, solid, gas, solution

)if it is found pure or in a compound

name the types of compounds it is found in

describe at least on method for purifying the element, include balanced equation showing how to purify the element if appropriate

7.Describe and write balanced chemical equations for at least one common reaction in which the element is involved.

8.Tell how the element is used today and how it was used in the past. You should try to find at least three uses total.

9.Give the economic importance of the element. For this item, think about ways the element is used. How would your life be different if this element was not available? Give specific reasons and exact details.Format:Your essay should have the following form:

1.Informative title

2.Introductory paragraph –states explicitly the “goal” of the essay. This paragraph might explain the background of the problem or posed question(s).

3.The body –here is where you address the guiding questions.

4.Concluding paragraph –reiterate what you set out to do and wrap things up.

5.References citedYou will submit your essay within Canvas. You will also be assigned two essays to peer review through Canvas. You should consult the rubric and make comments in the rubric and in the general comments box rather than making comments directlyin the paper.