b. Would it be possible to distinguish A from B by a chromic acid test? Circle One: Yes No c. What about A and C Circle One: Yes No d. Elaborate on your answers to (b) and (c) by indicating the color you would expect to see in a chromic acid test for A, B and C, respectively color of test? positive or negative? 3. Permanganate Test: Based on your understanding from the lab manual, would A and B be distinguishable by the permanganate test? CH Circle One: Yes No To elaborate on your answer, a. b. Describe the appearance of the test you would expect to see for each molecule If you believe one or both of the molecules tests positive in the presence of permanganate, circle the portion of the molecule(s) that is responsible for the positive test. color, precipitate? positive or negative? 4. If you thought A and B were indistinguishable by permanganate, is there a test you could perform to distinguish them? If you thought A and B were distinguishable by permanganate, is there an additional test you could perform to distinguish them? Your answer should include the test name and the results you would expect to see for A and B Test Name: color, precipitate? positive or negative?
3. The two molescules, A and B can be distinguished by permanganate test.
a) Molecule A contains a keto group and hence it can not be oxidised by potassium permanganate. So, if you treat the molecule with permanganate solution no reaction happens and the pink colour of potassium permanaganate does not decolorise.
Molecule B contains an aldehyde group and it is oxidised to carboxylate salt by potassium permanganate. Hence treatment of a pink solution of potassium permanganate with molecule B will decolorise the solution.
b) Molecule B gives positive permanganate test.
4. A and B can be distinguished by permanganate test.
Additionally they can be distinguished by Tollen\'s test.
A, being a ketine does not respond to tollen\'s test.(negative)
B, being an aldehyde responds to Tollen\'s test and a grey precipitate is obtained. (positive)
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