For 10 points, name this technique in which is used to determine molecular weights.
Two instruments that conduct this technique are separated by collision cells, and analytes of this technique are separated by quadrupole filters. Radical cations of the samples are generated prior to being subjected to this technique. The intensities of peaks in this technique's readouts are reported as proportions of the base (*) peak. Instruments to conduct this technique are often attached to upstream gas chromatographs. The presence of an "M+2" peak which is a third as high as the "M+" peak on this technique's spectrum indicates the presence of chlorine, because chlorine 37 is less abundant than chlorine 35. For 10 points, name this technique in which is used to determine molecular weights.
Two instruments that conduct this technique are separated by collision cells, and analytes of this technique are separated by quadrupole filters.
mass spectrometry [accept MS]