[FieraHD]

http://i.imgur.com/PwK1euk.jpg

Accidentally made this in the lab last week and have no idea what it is. We were supposed to be making p-nitroacetanilide, however we can still get full marks if we identify the molecule which makes no sense to me. 

[Arkcon]

Welcome, FieraHD: to the Chemical Forums.  According to the Forum Rules{click}, we want to see your attempt.

Probably the best way to get top marks on this question is to review an IR spectrum pf p-nitroacetanilide, and compare with this one.  Use published values for what functional groups the various peaks correspond to.

[FieraHD]

Hi, this is what I have done of the review of the IR so far: (We aren't required to review every absorption just the ones that should identify the compound.)

Peak 2 = A medium/strong absorption at 995cm-1 which most likely represents an alkene (=C-H) bend. However I would then expect to see an alkene stretch at around 3000-3100cm-1.

Peak 3 = A strong absorption at 1099cm-1 which could be a number of things the most likely of which would be an amine (C-N) however then a (N-H) amine group should be present at around 3300cm-1. Next on the likely candidates is an alcohol (C-O) bond which would be a strong absorption at 1100cm-1, once again however this can be dismissed as a broad absorption between 3000 and 3500cm-1 should be present. Finally others to be dismissed are an ether or ester as with both you would expect to see at least a (C-H) stretch between 2800 and 3000cm-1.

After these two I still didn't have any idea what sort of molecule this is, and all the other peaks are very weak absorptions. The spectra is nothing like the one for p-nitroacetanilide and I'm at a loss as to where to go from here other than if I were able to run NMR on it. (Unfortunately first years only have access to our NMR Suite at certain times during scheduled labs when we're doing other things.) I'm sure me and my lab partner are missing something extremely obvious haha.

[mjc123]

What did you use to make the p-nitroacetanilide? Can you list everything that might be in there, including solvent, catalyst if any, possible by-products? The simplicity of the spectrum, and the complete absence of any C-H stretching bands, suggests it might be inorganic - any possibilities? What phase is this material? Any colour?

[Furanone]

I think MJC might be right about it being inorganic for the reasons he mentioned. Is it possible it could be potassium sulfate based on the ingredients you used? Your spectrum stops at 650 cm-1, but if it went further to 400 cm-1 you could confirm. Also I use ATR for absorbance not transmission so maybe some differences. I also included sodium sulfate to show how it's missing the peak around 1000 cm-1. It's possible your peaks 7,6,5 & 4 are your organic material but in very small quantities, and 8 is noise like in my spectra.