Physical Characteristics of Vanilla Unknown Sample Questions

Physical Characteristics of Vanilla Unknown Sample Questions

Physical Characteristics of Vanilla Unknown Sample Questions

please complete the form attached for exp7 report using provided files. do not copy from internet.

Write a full answer for each question with explanation and details. I answered question 1 and 3 for you, you need to complete a full answer for 2, and 4 to 10. there are multiple spectrometer , please Don’t forget to interpret all spectrometers in the question 9 and 10.

Struggling to meet your deadline ?

Get assistance on

Physical Characteristics of Vanilla Unknown Sample Questions

done on time by medical experts. Don’t wait – ORDER NOW!

Meet My Deadline

Exp. 7 Report / Qualitative Organic Analysis Name:_________________________________ Score:______/ 20 1. Report the unknown number of the sample. # 60 2. Describe the physical characteristics of the compound. Powder, smells like Vanilla 3. Report the melting point or boiling point of the unknown. 82.7 C − 85.2 C 4. The Beilstein Test was positive or negative? Describe the observations. Negative Beilstein Test result 5. The combustion test was positive or negative? Describe the observations. Positive result for Combustion Test 6. The Tollens test was positive or negative? Explain the results. The Tollens test was positive. 7. Which derivative was synthesized? How was the derivative used in the determination? 8. Considering the physical tests (not spectroscopic) make a conclusion as to the identity of the unknown sample. Explain how you arrived at your conclusion. Give its name and draw its structure. 9. What spectroscopic data was acquired? Did it support or contradict the conclusion based on the physical data? Explain! (Be sure to assign and analyze all the data and include it with your report). 10. Considering both physical and spectroscopic data, make a conclusion as to the identity of the unknown sample. Give its name and draw its structure. Organic Chemistry Laboratory Basic Rules for Reporting IR, 1H NMR and 13C NMR Data Spectroscopic data provides valuable information about the structure of organic molecules. It is important to report this data in a conventional way so that it could be understood unambiguously. The paper print that you analyze is called spectrum (or spectra). It is not a picture, drawing, diagram, or chart. The “hills, bumps, spikes, or curves” are called peaks or signals. Each type of spectroscopy has its own set of rules to report obtained information. Following are the requirements for reporting IR, 1H NMR and 13C NMR spectra including examples of application of these rules to actual spectra of organic compounds. IR Spectra To report results of IR spectrum you need to start by reporting the method that was used to prepare the sample.Physical Characteristics of Vanilla Unknown Sample Questions

You could record IR spectrum of pure sample (report: neat), or you could use a specific organic compound to dissolve your sample and record it as a solution (report: Nujol, CCl4, etc), or you could ground it with KBr and press it into a tablet (report: KBr) and etc. Then you list recorded vibration frequencies; report these values to the closest cm-1. Do not list all of the signals in your IR spectrum. List signals that 1) correspond to significant functional groups and 2) identify your compound’s molecular structure. If you list more than one signal, list them in order of decreasing frequency. Next to the numeric value of frequency report intensity of the signal: s (strong), m (medium), w (weak). It should be followed by functional group assignment: list bonds in functional group responsible for absorption, e.g., C=O, -NH2, or –OH. Report should end with the units used to report frequency cm -1. Below is provided the IR spectrum of ethyl benzoate that was recorded as a solution in CCl4. After analysis of the spectra only the few important frequencies were identified. So IR spectrum is reported as follows: IR (CCl4): 3078 w(C-H aromatic), 2986 w (C-H alkyl), 1726 s (C=O), 1286 s (C-O), 1117 s (C-O) cm-1. 1H NMR Spectra To record an NMR spectra of an organic compound it is first dissolved in a solvent that does not contain any hydrogen atoms (such as CCl4) or in a solvent where all hydrogen atoms are substituted with deuterium. So to start reporting1HNMR results you first report the solvent that was used to dissolve the sample. Then you list all signals recorded in the spectrum. Report ppm values with appropriate number of significant digits (depends on an instrument used) starting with the highest one. Next to the numeric value indicate multiplicity of the signal: s(singlet), d(doublet), t (triplet), q (quartet), and so on. When it is hard to determine the exact type of signal m (multiplet) could be used. Multiplicity is followed by the number of hydrogen atoms (integration results) and assignment of hydrogen atoms in the spectrum to those in the structure. Below an 1HNMR spectrum of methyl 4-ethyl benzoate is provided that was recorded in CCl4. Signal (ppm) 8.00 6.93 3.89 2.60 1.25 Multiplicity d d s q t Integration results 2H 2H 3H 2H 3H The 1HNMR spectrum is reported as follows: Physical Characteristics of Vanilla Unknown Sample Questions

1H NMR (CCl4) ppm: 8.00 (d, 2H, aromatic ring), 6.93 (d, 2H, aromatic ring), 3.89 (s, 3H, OCH3),2.60 (q, 2H, -CH2- ), 1.25 (t, 3H, – CH2-CH3). 13C NMR Spectra Just like for 1HNMR, for 13C NMR you first report the solvent used to dissolve the sample, then you list all the shifts recorded on the spectrum starting from the highest ppm. Next to each shift assign the carbon in the molecule responsible for the signal in the spectrum. It is much easier to report carbons if you number the carbons in the structure. Below is provided 13CNMR spectrum of methyl 4-ethyl benzoate that was recorded in CCl4. Carbon numbers in the aromatic ring C1 C2 C3 C4 C5 C6 Shift (ppm) 127.3 129.8 127.6 148.6 127.6 129.8 The results of 13CNMR are reported as follows: 13C NMR (CCl4): 165.9 (C=O), 148.6 (C4- aromatic ring), 129.8 (C2 and C6 – aromatic ring), 127.3 (C1 – aromatic ring), 127.6 (C3 and C5 – aromatic ring), 51.5 (C-O), 28.2 (CH2-), 14.5 (-CH3). 39 QUALITATIVE ORGANIC ANALYSIS Experiment 7 Introduction asked to identify In this experiment, you will be issued an unknown aldehyde or ketone and spectroscopic it first through physical and chemical methods (Part 1) and then through the identity of methods (Part 2). A table of possible unknowns is provided. A claim as to before any the compound based on chemical methods must be submitted to your instructor spectroscopic methods may be employed. Part 1 —The Identification of an Unknown by Physical and Chemical Methods Wear safety glasses during the entire laboratory period and use gloves when handling any chemicals. All chemicals, reactions and procedures should be used or performed in the hood. All organic wastes should be put in the hazardouswaste bottle unless otherwise stated. 1) Preliminary Classification —Physical characteristicsof the unknown such as co or, offor, öhysical state and stallin form should be noted. Many compounds have characteristiccolors or odors, or they crystallizewith a specific crystal structure. Compounds with a high degree of conjugation are frequently yellow to red. Amines floral odor. Acids have a e odor. Esters have a pleasantsor often have have corrosive vapors some compounds of caution, sharp and ungent o or. As a note and should be snl ed with the greatest of caution. 2) Melting Point or Boiling Point Determination —The melting point or the boiling point of an unknown compound can be extremely useful since it will drastically limit the compounds that are possible. Consequently, it is very important that these values are determined as carefully as possible. Refer to your laboratory text for proper techniques.Physical Characteristics of Vanilla Unknown Sample Questions

If the melting point of a solid has a wide range (> 4-50C), it should be recrystallized. If the boiling point determinationyielded a wide range or if the temperature did not hold constant during the determination, it should be redistilled and a new temperature range determined. Allowances should be made for errors as large as +50C. 3) Flanze Tests – The Beilstein test and the quickly, Combustion 40 and they often give test can be performed easily and valuable information. using any flames in the Notify your instructor before organic laboratory!!!!!! a) The Beilstein Test —-A test for halides. Bend a small loop in the end of a short copper wire. Heat the loop end of the wire in a Bunsen burner flame. After cooling, dip the wire directly into a small sample of the unknown. Now, heat the wire in the B en burner flame again. The compoundwill first burn. After the burning, a reen flame wilVbé¯ßroduced if a halogen is present. For comparison, it may be useful to run the test on a sample known not to contain a halogen and on a sample known to contain a halogen. b) The Combustion Test —A test for aromaticity. Place a small amount of the compound on a spatula and place it in the flame of a Bunsenburner. Observe whether a sooty flame is the result. Compounds giving a sooty yellow flame have a high degree of unsaturation and may be aromatic. For comparison,it may be useful to run the test on a sample that is not conjugated as well as on a sample that does contain conjugation. 4) Classification Test —differentiation between aldehydes and ketones. Most aldehydes and ketones give crystalline solids when reacted with 2,4-dinitrophenylhydrazineor semicarbazide as demonstrated during the preparation of derivatives section that follows. However, only aldehydes will reduce chromium(VI)or silver(l). By these differences, you can distinguish between aldehydes and ketones. Both tests should be performed in case one is inconclusive. Tollens Test —The Tollens reagent must be prepared immediately before use. Note: Silver Nitrate is a skin irritant and can stain the skin. Wear gloves!To prepare the reagent, mix 1 mL of solutionA (describedbelow)with I mL of solutionB (described below) in a small beaker. A precipitate of silver oxide will form. To (NH40H) solution to dissolve complete the Tollens reagent, add 2 mL of ammonia In a separate container dissolve reagent). Tollens the silver oxide (This is now the mg (approximate) of solid unkown in 2 mL ofbis(24 drops of liquid unkown or 40 a little at a time, to a small Erlenmeyer flask ethoxyethyl) ether. Add this solution, Stir the mixture and warm gently on a hot containing 2-3 mL of Tollens reagent. If a mirror of silver is deposited on the inner walls of plate for about 5-10 minutes. aldehydesreduce ammoniacal positive. Most the Erlenmeyer, the test is precipitate of silver metal. nitrate solution to give a RCHO + silver 2Ag + RCOONl-14 + 1-120+ NH3 g of silver nitrate in 3 mL of water. Solution A: Dissolve 0.3 10% sodium hydroxide solution. Solution B: Prepare a 41 of correct identification the of tests principal the chemical 5) Preparation ofDerivatives- one of the compound by aderivative. convert to trying in comes compound unknown an compound is called a compounds. reaction to another known compound. This second otherwise very similar yourPhysical Characteristics of Vanilla Unknown Sample Questions

The derivative is a way of distinguishingtwo or 2,4-DNP) based on the (semicarbazone make to derivative best Select the derivatives as provided in of suspicions of unknown identity and the melting points following tables. Dissolve reaction as you see fit) a) Sonicarbazones —(you can adjust the scale of this sodium acetate in 1.3 mL of 0.25 g of semicarbazidehydrochloride and 0.38 g of ethanol. Mix the two water. Then dissolve 0.25 g of the unknown in 2.5 mL of heat the mixture for solutions together in a 25 mL Erlenmeyer flask and gently After from heat. about five minutes. If the solutionbegins to boil, remove it formed, scratch has heating, place the reaction flask in a beaker of ice. If not solid of the derivative. the sides of the flask with a glass rod to induce crystallization recrystallized Collect the derivative by vacuum filtration. If necessary it can be from ethanol. scale of this reaction b) 2,4-Dintrophenylhydrazones (2,4-DNP) – (you can adjust the of in 7.5 mL as you see fit) Dissolve 1.5 g of 2,4-dinitrophenylhydrazine 95% of concentrated sulfuric acid. In a beaker mix 10 mL of water and 35 mL solution ethanol. With vigorous stirring, slowly add the 2,4-dinitrophenylhydrazine the to the aqueous ethanol mixture. If solid remains after thorough mixing, filter 2,4-DNP solution by vacuum filtration with a Hirsch funnel. Place 10 mL of the 2,4-DNP solution in a test tube and add an estimated 1 mmol of the unknown compound. If the unknown is a solid, it should be dissolved in a minimum amount of 95% ethanol or 1,2-dimethoxyethane before it is added. If crystallization is not immediate, gently warm the solution on a hot plate and then set it aside to crystallize. Collect the product by vacuum filtration. 6) Other tests may include the determination of density, refractive index and solubility. 7) Conclusionsfrom Physical and Chemical Methods —Considering all of the data, make a conclusion as to the identity of your known sample. After submitting your answer to your instructor, you may request a genuine sample of the compound for comparison. You may perform any of the physical and chemical methods of analysis on the genuine sample that would be useful. However, you should consider trying mixed melting point for solids and IR and/or mixed gas chromatography for liquids. 43 ALDEHYDES COMPOUND BP MP in Celsius in Celsius Ethanal Pro anal Pro enal 21 48 52 2-Meth I ro anal Butanal 64 75 MP of the SEMICARBAZONE 162 89 171 125 95 MP of the 2,4-DINTRO PHENYLHYDRAZONE 168 148 165 187 123 123 106 3-Meth Ibutanal Pentanal 2-Butenal 2-Eth Ibutanal Hexanal He tanal 92 102 104 117 130 153 107 2-Furaldeh de 162 202 212 2-Eth Ihexanal Octanal 163 171 254 Benzaldeh de 179 114 106 237 Phen lethanal 195 2-H drox benzaldeh de 4-Meth Ibenzaldeh de 3,7-Dimeth 1-6-octenal 197 204 207 2-Chlorobenzaldeh de 4-Methox benzaldeh de Trans-Cinnamaldeh de 213 248 250 decom 2-Methox benzaldeh de 4-Chlorobenzaldeh de 3-Nitrobenzaldeh de 4-Dimeth laminobenzaldeh de Vanillin 4-Nitrobenzaldeh  Physical Characteristics of Vanilla Unknown Sample Questions