Furaldehyde semicarbazone msds

Combined products creates lower melting point than either individual compound?

2018.09.19 04:46 tekkado Combined products creates lower melting point than either individual compound?

Morning fellows, just curious and sorry if this seems like home work help but have a general inquiry.
Im writing up my lab report and going over my melting point results for a handful of compunds as follows:
Cyclohexanone Semicarbazone: 169.9 C
Furaldehyde Semicarbazone: 215.3 C
Competitive Thermodynamic rxn Mixture of both: 166.9 C
Competitive Kinetic rxn Mixture of both: 179.7 C

So from my spectra I know that the major product in the thermo run was Furaldehyde Semi and the major product of the kinetic run was Cyclohexanone Semi. I think I understand that with some amount of furaldhyde in the kinetic mixture this would cause the melting point to rise but for the thermo run why would the temp be lower than even the original recorded value of cyclo?
Other than bad lab technique?

Thanks
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2014.12.05 18:36 Lucas0402 [Organic Chemistry] Potential Energy Diagrams

Hello. Thank you for reading. I am struggling through an Organic Chemistry class at night while working two jobs. It is the last prerequisite before I can apply to go back to school for what I want to. I prepared this lab write-up a couple weeks ahead of time and after completing it last night I am struggling to write the conclusion. I will copy/paste the lab report (typed before transcribing into lab book) here. Everything is my words until "conclusion" where I typed the professors instructions to include in the conclusion. I have no idea where to go from here. I tried looking up Potential Energy Diagrams and I am sweating I am so lost. I have to turn in my lab book Tuesday for final grading. I HAVE to get a B or its all for nothing. Please help! Kinetic & Thermodynamic Reaction Control in Competing Reactions Leader: Equilibrium is usually not achieved between the products and the beginning materials in most organic reactions. This means the major product is a result of kinetic control. If the same reactions were under equilibrium conditions, the final product may be very different. The reaction between aldehydes & ketones with semicarbazide exemplify the different effects these factors can have. In this reaction, acidity beyond a certain point causes a precipitous drop in the amount of free semicarbazide through salt formation. In turn, the low nucleophilic activity of the cation results in a reduced rate of the reaction. However, because the carbonyl compound is subject to the addition of a proton to the carbonyl group, the electrophilic activity is enhanced, thus the rate of reaction in increased. The concurrent presence of these two reactions cause a window of ideal acidity in which the reaction rate is optimum, while just outside this pH range the rate abruptly drops. Some semicarbazones, such as thiosemicarbazones and nitrofurazone, are known for their anti-viral and anti-cancer properties in the body. These effects are facilitated by means of binding the semicarbazones to iron found within cells. Buffer solutions, commonly sodium acetate or phosphate, are involved in reactions between carbonyl compounds and reagents in the formation of such derivatives as semicarbazones, arylhydrazones, and oximes. Combining 2-furaldehyde and cyclohexanone under kinetically controlled and equilibrium conditions, both reactions in formation of semicarbazones will be observed. Under kinetic control, the formation of semicarbazones will be much faster, while under equilibrium there will be a greater amount of semicarbazones formed. Table of Physical Constants: (I deleted this after copy/paste because it was a formatting mess) Reaction & Mechanism: Kinetic & Thermodynamic Reaction Diagram Procedure: 1. In a 125 mL flask, dissolve 2 g of semicarbazide hydrochloride and 4 g of dipotassium phosphate in 50 mL of water. 2. In a small flask, mix together 1.9 g of cyclohexanone, 2.0 g of 2-furaldehyde and 10 ml 95% ethanol. Place half of the solution in one small test tube and half in another small test tube. 3. In a 50 mL Erlenmeyer flask, place 25 mL of the semicarbazide solution and cool it to 0-5°C in an ice bath. In the same cooling bath, chill one of the test tubes containing the furaldehyde-cyclohexanone solution. 4. Empty the chilled contents of the test tube into the semicarbazide solution and mix them well. Crystals will form quickly. Place the flask back in the cooling bath for 5 minutes and then filter the crystals with suction. Wash the crystals with 5 mL of cold water. Dry the product thoroughly. Weigh crystals and determine the melting point. Label as product number 1. 5. Place the remaining 25 mL of semicarbazide solution in a 50 mL flask and heat it to 85°C. 6. Add the 2-furaldehyde-cyclohexanone solution from the second test tube and swirl the solution. Heat the flask for 15 minutes before allowing the solution to reach ambient temperature. 7. Chill the reaction mixture in an ice bath for a few minutes. Collect the crystals with suction. Wash them with 5 mL of cold water. Dry the product thoroughly, record the weight and determine the melting point. Label as product number 2. Observations & Data: Amount semicarbazide used 2.2 g Amount dipotassium phosphate used 4.02 g Amount cyclohexanone used 1.83 g Amount 2-furaldehyde used 2.4 g Product #1 weight 0.39 g Product #1 melting point 130-180 °C Product #2 weight 0.55 g Product #2 melting point 195-210 °C Conclusion: Which semicarbazone is each product? Account for the results that you have observed. Include Potential Energy diagrams with your explanations.
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