Description     **** This part right here it’s the way that the teacher wants the introduction to be done. CH210L Topics to be covered in the Introduction Section Expt: 3.4 Melting Point/Mixed Melting Point/Unknown Determination 1. Explain the process of melting. Make sure to include the types of bonds that are breaking when an organic compound melts. 2.    Three test tubes, labeled A and B, contain substances with approximately the same melting points. a.    If A and B are different compounds, what would you expect to find if you took a melting point of a mixture of the two? b.    If compound A had a melting point of 123-124ºC and compound B a melting point of 123-124ºC, what could you conclude? 3.    Why should melting points be reported as a range rather than a single temperature value? 4.    What is the effect of an insoluble impurity, such as sodium sulfate, of the observed melting point of a compound. NOTE 1. Footnote when appropriate. 2. Make sure you include the unknown #’s when referring to your unknown compound. 3.    In the Procedure, be clear as to what was done. Reference the appropriate procedure(s) in the book making sure (especially for this lab) to specify modifications/changes. In other words, make it clear what you did and later on what the results were. 4.    In the Results and Discussion section, make sure to comment on/discuss (not just restate in words) your results. Note: “results” does not refer here to just the product, but also to how the process worked in terms of results AND process. In other words, make reference to what actually transpired when you took various melting points. Make sure to explain in words how you identified your unknown. 5.    Finally, this lab report is due Section A, B, C, D Wednesday October 28th in lab Section F, G, J, K Thursday October 29th in lab Section L, M     Friday October 30th in lab ****This part right here that’s what happen in lab.please read carefully. We did experiment 3.4 Melting point determination with an unknown -identify your unknown by MPE mixed MP 1-Melting point of an unknown 2-Mixed melting point of an unknown + like known 3-Mixed Melting point of an unknown + unlike known Also take melting points of three benzoic acid products from previous lab compare to lab ttext value of 121.5-122 C The first part of the experiment I used unknown number 50. unknown number 50 melting point was from 135.8-137.2 the second part of the experiment I used the same unknown number 50 + maleik acid .This part of the experiment Maleik acid waited less than a minute to dissolve so the melting point was less than 113. I took the same unknown and mixed it with Acetyl salicylic that time around the melting point was 94.9-100.6 the third time around I took the same unknown which was unknown # 50 I mixed it with Benzoid acid at that time I found out the unknown was made with benzoid acid because it has almost the same melting point with the unknown # 50 when I did the melting point. The melting point of the unknown + the benzoid acid was 132.1-135.4 one part of the question of the lab where we had to take the melting point of three benzoic acid from the other lab. the answer to those benzoid melting point was first in the other lab the melting point of benzoid acid in the first point of the lab was 1-Benzoid acid,with vacuum filtration the melting point was115-126.1 2-Benzoid acid water + pasterur pipette? with filter , the melting point was 108.9-125.8 3-Benzoid acid with methanol /water, vaccum filtration was 105.6-129.2 **** Please do not include cover page in my report because I will be doing this on my own.and also in procedure state that the procedure was taken from macroscale and microscale organic experiments by kenneth L. williamson .Robert D.minard Katherine M.Masters from page 38-54 LAB REPORT FORMAT General information: •    lab reports are written up individually •    lab reports are due one (1) week after the experiment has been completed and are turned-in at the beginning of the lab. [reports will be accepted one wk late with a 10% penalty, after the one late wk, not accepted (grade of 0)] •    lab reports are to be typed (word processed) •    except for the introduction section, lab reports are a report of what you did, therefore, are written in the past tense. • lab reports are written in formal English which includes complete sentences and proper match of subject and verb plurality. •    keep brief , but cover needed material (3-5 pages, not incl. Cover page) •    NOTE: Plagiarism will not be accepted! Be sure to cite full references, where appropriate. Paraphrase. Keep quotes to a very minimum; however, if used, use quotation marks, with reference. General format: Cover page: Centered, middle of page Experiment No. Experiment Title Centered, bottom of page Student Name Course number [CH 210L or CH211L] Lab Section (A, B, C, D, F, G or J) Date experiment performed I. Abstract: A short paragraph describing the objectives of the experiment and the results. Include: objective(s) of the experiment (main reasons, purposes for the experiment) and major (key) results (findings) of the experiment. If an unknown was analyzed, give its unknown number and identity [for example, unknown #24 was identified as benzoic acid]. For synthetic experiments, include the name and structure of the final product and %-yield. Include the name of all Named Reactions (e.g., Diels-Adler Reaction, Grignard Synthesis, Aldol Condensation-Claisen/Schmidt Reaction). [Do not give a mini-procedure, nor analysis of results.] NOTE – THE BRIEF SUMMARY OF RESULTS MUST CORRESPOND TO THE OBJECTIVES. By that I mean if you propose to do something, the results should correspond to the objective. **** this right here please this is a format that the teacher wants the lab to be done. II. Introduction: (Background information about the experiment, i.e., ONLY MATERIAL KNOWN BEFORE THE LAB WAS CARRIED OUT.) In this section you will answer questions provided by the instructor NOTE: Even if the instructor does not specifically include it with his/her instructions, the introduction for all synthetic experiments [e.g., dehydration of 2-methyl-2-butanol in Ch 210L and all of Ch 211L] will include all reaction(s) of the experiment and a detailed mechanism for the reaction(s). NOTE: The detailed mechanism is hand drawn for the specific reagents and products relevant to the lab. In other words, do not copy a generic mechanism from the web! Also, for all multi-step product isolation/purification experiments [e.g., Expt 7.1 and others as indicated in the syllabus for the pre-lab], the introduction should include a flow diagram for the procedure. NOTE ALSO: Do not plagiarize. Use in text citations, e.g., (Williamson, p xx) and then give a full citation at the end of you lab report in the “Works Cited” section. See below for format. III. Experimental Section: The experimental section includes two parts. Procedure and Changes/Modifications to the Published Procedure Use the format: The procedure was taken from Williamson, pages xx – yy, with the following modification(s): [list them in bulleted complete sentences. Note, this section should reflect what you actually did and include changes and additions to the published procedure, such that the reader should be able to duplicate your work following the directions above. If the report includes a Table of Known Data (used for identification of unknowns), the table belongs here. Reaction and Theoretical Yield Calculation (Only for labs that something is made.) The last part of the experimental section is the reaction and theoretical yield calculation using the amounts actually used. If they were the same ones in the lab manual used to calculate the pre-lab value, just copy them directly out of your lab notebook. [Note the differences between the one given below and the one in the Notebook Format Sheet.] C5H6 C4H2O3 C9H8O3 mol 0.00242 0.00224 [LR?] 0.00224 MW 66.10 98.06 164.16 g 0.16 0.220 0.368 [TY??] mL 0.20 – – d 0.80 – – IV.    Results and Discussion: (DATA and ANALYSIS) Data – Give original data and calculated values with appropriate units in an organized tabular format where possible. Note: Data includes all relevant observations (i.e., heat evolved, colors, temperature range that a distillate was collected, etc.) as well as the more obvious, such as mass of vial, mass of vial + sample, mass of sample, melting point range, boiling point, etc.). If a lab includes generation of a TLC plate, a GC trace, or an IR spectrum that you made in class, the original should be attached to your lab report; however, note that data such as Rf’s, retention times, absorption frequencies, should be included in tabular form in the data section and then discussed in the following analysis section. Analysis – Discuss/analyze the results. Do NOT just restate the results; explain how the results are consistent or inconsistent with the introduction. The analysis explains HOW the data allowed you to draw various conclusions. Do not make statements without including/discussing the supporting data that led to that statement. If there is an unknown, explain in words how the unknown was identified. Unless you made an obvious mistake like dropping half the crystals on the floor or being unable to dry the sample in the allotted time, do not discuss errors. There is no error analysis section. NOTE: The analysis section is generally worth 10-20% of the lab report grade and should be a minimum of a half page of text. V. Works Cited – Format: 1.    Williamson, Kenneth L.; Minard, Robert D.; Masters, Katherine M. Macroscale and Microscale Organic Experiments, 5th ed., selected chapters; Houghton Mifflin Co.: New York, 2007. NOTE: Section V. Works Cited should follow directly from Section IV. Results and discussion. Do not put Works Cited on a new page as you are told to do in English class. Chemists do not waste space and trees. **** this is a sample lab from another student provided by our teacher .This shoul be a guide to our lab reports. I. Abstract: The objective of this experiment was to reduce nitrobenzene with tin and hydrochloric acid to produce the anilinium ion, which was then converted to aniline by reacting it with sodium hydroxide. After steam distillation, the distillate, containing aniline and water, was reacted with acetic acid and sodium acetate to produce acetanilide. 1.999 grams (60% yield from nitrobenzene) of acetanilide was collected as white flakey crystals. The melting point of the product was 112.7-113.6 ?C. II. Introduction: Nitrobenzene can conveniently be reduced to aniline hydrochloride with tin and HCl. The tin acts as the reducing agent (source of electrons), while the HCl provides the hydrogen atoms. Free aniline can be formed by the treatment of the hydrochloride with a solution of alkali (Williamson pg. 609). Treatment of the aniline with acid gives the water-soluble anilinium ion. “The anilinium ion reacts with the acetate ion (from sodium acetate) to set up an equilibrium that liberates a small quantity of aniline. The aniline reacts with acetic anhydride to give acetanilide” (Williamson pg 609-610). The proposed mechanism (Williamson pg 609-610) for the conversion of aniline to acetanilide is shown below. Should one continue this series of reactions to make the antibiotic sulfanilamide, the next step is an electrophilic aromatic substitution of acetanilide with chlorosulfonic acid. The aniline is protected with the acetyl group to prevent reaction of the amine group with chlorosulfonic acid and to ensure that the amine is not protonated and thus a meta-director to substitution (Williamson pg. 609). Detailed mechanism (show starting materials, products, and all organic intermediates) included here. Make sure all structures are connected by arrows showing the flow of electrons. II. Experimental Section: Procedure: The procedure was taken from Williamson, page 615: 2. Macroscale Preparation of Aniline and, page 616: 4. Acetanilide: Acetylation in Aqueous Solution with the following modification: ¼ scale quantities of all reagents were used. When the aniline which is a clear liquid was prepared, it was not pure as indicated by the yellow color. The impure aniline was treated with charcoal. The crude aniline was mixed with 2 mL of 3M HCl and 0.5 gram of charcoal, heated in the presence of a boiling stick to 90 ?C and filtered while hot to remove the charcoal. The charcoal was rinsed with 2 mL of hot water. Reaction and Theoretical Yield Calculation: Experiment 45.2 Structures of the organic molecules included here: C6H5NO2     Sn     HCl     C6H7N mol.     0.0245[LR] 0.0527 0.166     0.0245 MW 123.11 118.69 12M 93.12 g     3.02 6.25 – 2.28[TY] mL 2.70 – 13.8 2.33 d 1.12 – – 1.02 Experiment 45.4 Structures of the organic molecules included here: C6H7N     C4H603     NaOAc C8H9NO mol. 0.0245[LR] 0.0527 0.166     0.0245 MW 123.11 118.69 12M 93.12 g     3.02 6.25 – 2.28[TY] mL 2.70 – 13.8 2.33 d 1.12 – – 1.02 III. Results and Discussion: Data: •    When the tin, nitrobenzene, and con. HCl were added to the reaction flask, the solution turned yellow, gave off a strong odor, and became hot. •    At the end of the reaction, the contents were hot and cloudy. When the alkali was added, the solution thickened and turned gray. Water was added until the flask was half full the aniline was steam distilled. The distillate was a yellowish, milky substance. •    Treatment with charcoal and hot filtration gave clear aqueous solution of aniline. •    When the acetic anhydride was added white crystals were quickly formed. Mass of empty boat 2.376 g Mass of boat and product    4.375 g Mass of final product     1.999 g % Yield     60% Melting point range     112.7-113.6 ?C (compared to the literature value of 114 ?C [Williamson, pg 611]) **** Please if there’s any question that the writter required to write a better lab report please email me at mylovedith@yahoo.fr .this lab is due this thursday 29-2011. I want a well written lab report and I did include everything that happen in lab to this lab report. Analysis: Experiment 45.2 involved synthesizing aniline by reduction of nitrobenzene with tin and hydrochloric acid. The reaction was exothermic and produced a chalky solution. The reaction mixture was neutralized with strong base, and the aniline was isolated by steam distillation as a yellowish milky liquid. Treatment with charcoal and hot filtration gave clear aqueous solution of aniline which was then reacted with acetic anhydride and sodium acetate. After standing and cooling, white crystalline acetanilide was isolated by vacuum filtration to give a 60% yield from nitrobenzene. The melting point range was found to be 112.0-113.6 ?C (compared to the literature value of 114 ?C [Williamson, pg 611]). Because the experimental melting point was quite narrow and close to the literature melting point (previous work with this same melting point apparatus consistently gave results about 0.5 ?C lower than expected), it is clear that fairly pure acetanilide was synthesized in this experiment. If the experimental melting point was broad and lower than the literature melting point, it would indicate impurities were present in the product. V. Works Cited: Williamson, Kenneth L.; Minard, Robert D.; Masters, Katherine M. Macroscale and Microscale Organic Experiments, 5th ed., selected chapters; Houghton Mifflin Co.; New York, 2007.
Spacing    Double