Metal Acetylacetonate complex PDF

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Experiment 4 Report

Na me :Cl a r aMi n d j i mba

Partner: Olivia Nadalini

St u d e n tNo :2 0 1 66 8 6 2

Student No: 20146595

La bSe c t i o n :2 7

Be n c h#( o nc o mp u t e rs c r e e n ) :7

Experiment 4. (2 weeks) (LSM) Metal Acetylacetonate Complex Purpose [For part 1 of the experiment, the purpose was to make a crude metal acetylacetonate complex, Fe(acac)3, or tris(acetylacetonato)iron (III) through organic synthesis. For part 2 of the experiment, the purpose was to recrystallize the complex we primarily made, determine its melting point, and determine percent yield compared to the crude product. percent yields.]1

Introduction [For this experiment, we will be deprotonating acetylacetonate to make an acetylacetonate anion, which can coordinate with iron (III) to form Fe(acac)3. A brief background knowledge required for this lab would be to understand what coordination complexes are. These complexes can be formed by allowing a metal ion to bind with neutral molecule or an anion. The neutral molecule, or anion, will be donating electrons to the metal ion, forming a strong bond between the two. ]

Procedure Synthesis of Fe(acac)3 1

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1. Obtain approximately 1.00 g of FeCl3•6H2O directly into Erlenmeyer 9ask. 2. Add 15 mL distilled water, then place it all on the stirrer/hot plate. 3. Add 5 mL of methanol, and 2 mL of acetylacetone into a 50 mL beaker, then ass it to the iron chloride solution. Stir throughout manoeuvre. 4. Obtain approximately 2.5 g of sodium acetate into a 50 mL beaker, add 10 mL of RO water, then add this to the red solution once it has dissolved. Stir rapidly. 5. Heat the solution at ~70 degrees Celsius for 10 minutes, then cool it down on the bench for another 10 minutes. 6. Filter product using the vacuum filtration. 7. Transfer the dried product onto the watch glass and record the mass of the watch glass + paper + product. Recrystallization of Fe(acac)3

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1. Transfer 0.3 g of product from part 1 into a 50 mL beaker, then place it into a hot water bath. 2. Obtain 10 mL of methanol into a 150 mL beaker and place it in a water bath at 7-80 degrees Celsius. 3. Add hot methanol to the 50 mL beaker until the product has completely dissolved. 4. Place beaker with its dissolved product in a hot water bath until crystals start to appear, then remove and let it cool. 5. Obtain 5 mL of methanol in a 50 mL beaker, and let it chill in an ice bath. 6. Filter the product using the filtration unit for 5 minutes. 7. Weigh watch glass, then watch glass AND product. Record the mass. 8. Using the Mel-temp apparatus, find the melting point of the dry recrystalized product and the crude product.]

Observations [Part 1: During Step Four, we observed that the solution was a bright yellow/orange. During Step Seven, as soon as the acetylacetone was added, we observed that the mixture instantly became dark red, and had a very strong odour. During Step Nine, we observed that acetate is a white powder, which completely dissolved with water. When added to the solution, we observed that the mixture became very thick, smoothie like, and changed colour from dark red to light red. During Step Ten, we observed that as the mixture is heating up, it becomes darker. In addition to its gradual colour change, we observed that there were gas bubbles, and that a precipitate was slowly forming. During Step Fourteen, we observed that the filtration allowed for a light red, solid, and sparkling powder to appear to us. Part 2: During Step Four, we observed and made a note that our large hot water bath’s temperature was a little too low when putting the methanol in it. During Step Five, when we were adding the methanol to the crude product, we observed that the product dissolved very instantaneously, and it became a dark solution. As it was heating up in the hot water bath, we observed that some of the solution was evaporating. And when we let it cool down on the bench, we observed a lot of Brownian motion in the first tiny crystallites as they floated on the surface.

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During Step Six, as we cooled the mixture even further by putting it in an ice bath, we observed that a lot of the mixture was crystallizing.]

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DATA SHEET

Crude Fe(acac)3 Experimental Observations: [These should be written directly into your lab notebook.] Mass of FeCl3∙6H2O /g Mass of watch glass /g Mass of watch glass and crude product /g (before recrystallization) Recrystallized Fe(acac)3 Mass of watch glass /g Mass of watch glass and pure product /g (after recrystallization)

1.06g ± 0.01g 34.31g ± 0.01g 36.24g ± 0.01g

27.48g ± 0.01g 27.61g ± 0.01g

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Calculations

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Questions From Part I 1. What is the limiting reagent? [The limiting reagent of this experiment is FeCl3∙6H2O (See calculations above).] 2. What is the percent yield of the crude product? [The percent yield of the crude product was 137.2 % But I know this is not right. I checked for calculations errors, and there were none, therefore the solution must be impure.] 3. Give three reasons why you did not get 100% yield. [ 1. Final product must be impure and has residuals of chemicals that were supposed to disappear. 2. Some crystals do not crystalize out of the solution, and they remained in the solvent. 3. Product being lost in the transfer between different apparatuses.] From Part II 4. What is the percent yield of the pure product? [Percent yield of pure product is 59.4% (see calculations above).] 5. Compare your crude vs. pure product yield. List three reasons why they may be different/same. [ 1. Overheating the solution, resulting in methanol evaporating, as well as some of the product, which would decrease the percent yield. 2. If pure product was not mixed enough, and was not given enough time to recrystalized, this would result in a decrease of the percent yield. 3. Product being lost in the transfer of apparatuses throughout the experiment.]

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What can you say about the difference, if any, between the crude and the recrystallized product in your observed melting point data?

[Crude product T1: 162 degrees Celsius. Crude product T2: 164.3 degrees Celsius. Recrystalized product T1: 181.7 degrees Celsius.2 Recrystalized product T2: 183.2 degrees Celsius.2

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The recrystalized product had a much higher melting point/range than the one of the crude product.]

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References [Each reference listed here should have a number that corresponds to the superscripted number in the body of the report where this reference is pertinent.] 1.

[First- Year Laboratory Manual Chemistry 112. 2019-2020 edition. P.59-65]

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[Galen Richardson and Braeden Schorbus on computer #8.]

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