[nkhaliq]

Hello, I am currently taking organic chemistry, first semester.
Recently, in lab, we oxidized a secondary alcohol to a ketone. The alcohol was given to us as an unknown.

The first thing we did was generate hypochlorous acid (HOCl) by reacting household bleach (NaOCl) with acetic acid. We then reacted the hypochlorous acid with our unknown secondary alcohol to generate our ketone. After this, we carried out a number of experiments to figure out the identity our ketone and in turn our unknown alcohol. I did everything the way the manual recommends but the data I collected is so conflicting that I can't make any conclusive decisions.

After drying the ketone product from the procedure described above, I purified it using simple distillation. the distillation started at 82 degrees Celsius, and remained at this temperature for quite some time. However, the temperature then started to rise and steadied at 102 degrees Celsius (I'm assuming there are two different products being distilled, one at 82 and the other at 102-but what if it's water that's distilling at 102?). At this point, the professor told us to stop the distilling. we collected our distillate but I've no idea what ketone it is because the boiling point range is so large! Looking the table provided, it could be butanone (bp 82 deg Celsius), 3-methyl-2-butanone (bp 94 deg Celsius), 2-pentanone (bp 102 deg Celsius), 3-pentanone (bp 102 deg Celsius).

We tested our purified ketone to see if it was a methyl ketone by performing the iodoform test. I did the positive control test using acetone and a yellow precipitate formed, indicating the presence of a methyl ketone. When I repeated the steps using my unknown purified ketone, a pinkish solution was observed. I repeated the test again and got the same results. No yellow precipitate formed so I concluded I did not have a methyl ketone.

Next, I converted a little bit of my ketone to semicarbazone derivative by reacting it with semicarbazide. A white precipitate formed. I purified this precipitate further by recrystallizing it in 95% ethanol/water mixture, collected the crystals and left them to dry.

I also converted some of my purified unknown ketone to 2,4-dinitrophenylhydrazone derivative by reacting it with 2,4-dinitrophenylhydrazine. I collected the crystals, recrystallized using 95% ethanol, collected the crystals and left them to dry.

In the next lab, I took melting points of the 2,4-dinitrophenylhydrazone derivative and semicarboazone derivative, and got 117 and 110 degrees Celsius respectively. Here's a link to a table: http://userhome.brooklyn.cuny.edu/ghorowitz/documents/Alcohol.pdf

I am not sure how to narrow down to the possible ketone and then to the alcohol because each test points to a different ketone. Can someone please help me? I need to identify my unknown correctly or i'll lose major points.
Thanks in advance!