"ANALYSIS OF MASS SPECTROMETRY DATA: MIXTURES OF ALCOHOLS, ITERATIVE METHOD. Each peak height H[i] of a mass spectrum can be decomposed into contributions from each component's partial pressure P[i] ■ H[i] = r[i1]*s[1]*P[1] + r[i2]*s[2]*P[2] + .... ■ where r[i,j] is the experimentally determined relative contribution from each known component and s[j] is the sensitivity factor for a given component. In general there are many more peaks than components so the system is 'overdetermined'. *** Answer(s) to Problem(s) **** (c) Copyright PCSCC, Inc., 1993Component 1 is methanol, 2, ethanol, 3, propanol and 4, butanol. Experimentally measured R[i,j] and S[j] are supplied. Set P[i] to 0.0 and set H[i] to known values. Must solve as nonlinear because (more equations (5) than unknowns (4) ).Type W and use default tolerance, type (enter). Results MOLE[1]=0.25, MOLE[2]= 0.23, MOLE[3]=0.26, MOLE[4]=0.26. Type any key to exit. ||Determine the mole fractions of the 4 alcohols: methanol, ethanol, propanol and iso-propanol if the mass spectrum yields 5 peaks with mass/charge and heights of: (19, 5.10), (29, 29.75), (31, 100.0), (39,5.08) and (59,6.80). The relative intensities and sensitives are supplied. (from Dickson, T. R., The Computer and Chemistry, Freeman, San Francisco, 1968). Type comma key to see entire comment. Type (F2) to return to application file."
