Analysis Of Potassium Permanganate Test

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Potassium Permanganate Test:
1. Three drops of the compound to be tested are dissolved in 2 ml of water or aqueous ethanol. 2% KMnO4 solution (a purple solution) is added drop wise and the solution is shaken.
2. The purple color of the KMnO4 solution disappears and a precipitate of MnO2 is formed. A negative test is if there no precipitate.
3. Repeat for every unknown and record observations.
Observations and Results
Water Solubility Test:
When the test was conducted and observations were made, compounds 6 and 7 formed two layers, indicating that they are not dissolvable in water. Compounds 8, 9 and 10 where dissolved.
As indicate earlier, if a compound does not dissolve in water, it is a negative test and if it does, it is a positive test.
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Compound 7 formed two layers as well, but both were yellow. Compound 8 formed a very dark red colour. Compound 9 also turned the solution red. Compound 10 did not react with the solution, so the colour stayed yellow.
Compound 6, 8 and 10 turned the solution a dark red colour, meaning a positive test charge, and compound 7 and 9 did not change the colour from yellow, meaning a negative test charge.

Chromic Acid Test:
When this experiment was conducted, compound 6 and 8 turned a dark blue-green colour, and compounds 7, 9 and 10 stayed orange.
Compound 6 and 8 turned the solution a dark blue-green colour, meaning a positive test. Compound 7, 9 and 10 did not change the colour from orange, meaning a negative test result.
Unknown # Observations Results
Compound 6 Dark green-blue Positive
Compound 7 Orange Negative
Compound 8 Dark green-blue Positive
Compound 9 Orange
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I concluded from Cerric Nitrate, Chromic Acid, Ion Chloride and Potassium Permanganate tests that the compound cannot be an aldehyde, primary or secondary alcohol, alkene or contain a phenol group. DNPH and Iodoform test positive, meaning that the compound can be aldehyde, ketone, acetaldehyde or methyl ketone. However, since I it is known that cannot be an aldehyde, therefore it is a ketone containing a methyl group. Since it is now for sure that compound 7 is a ketone, it was clear that it will contain a C=O group, so the only reason for it to result negative in the first test is that it contains more than 4 carbons. Using the boiling point, I was able to confirm that it is a ketone with more than six carbons (except 3-3,dimethyl-2-butanone because its boiling point is 103oC and it should be less than 110oC) Therefore, compound 7 is a ketone that has six or more than six carbons and contains a methyl group.
From the first three tests I was able to identify that compound 8 is a small primary or secondary alcohol and using the DNPH and Iodoform test, I concluded that it is not a ketone or aldehyde. The fourth and last tests helped confirm that the compound is a phenol and contains double bonds. Even though it is supposed to be a small molecule with less than three carbons, due to its ring structure and the double

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