how do you find a chemical shift of an unknown arene?

Question

I am trying to find the absorptions and chemical shift of an unknown arene?

Answer 1

You would need the structure to estimate a chemical shift, or vice versa.  An aryl hydrogen would show a C-H peak in an IR spectrum just after 3030 cm^-1 and C=C peak around 1500-1600.  HNMR and CNMR chemical shifts can vary a good deal depending on the structure.

Answer 2

Are you doing IR spect? 

 

In spect, you need to check the absorption charts and look to see if there are absorptions in the fingerprint region.