mass spectra problem. i am reading a mass spectra, attempting to map a polypeptide of length of about 10 units. i have discovered that the first amino acid residue is an arg. the range of possible amino acids for the next peak of the B series (bn-2) does not correspond, meaning that the peaks that are present either don't make sense as molecular weights OR do not correspond to a y series (y 2) peak. i'll see if i can post a picture. but if you can help me trouble shoot this reading i would greatly appreciate it!

Question

anonymous · Answer

here is the mass spectra. the number cut off in the bottom left corner is 603.2

anonymous · Answer

figured it out. forgot that the oxygen on the carboxylic acid functionality is gone and i have to adjust the mol weights accordingly

anonymous · Answer

okay......i was trying to also work it out myself.....