1. For the determination of benzene, toluene, ethylbenzene and xylene isomers in water by gas chromatography and flame ionization detection (CG-DIC) the following conditions were used: capillary column 30 m x 0.25 mm, with nonpolar stationary phase ( 5% phenyl, 95% dimethylpolysiloxane, 0.25 um of film thickness), injection of the sample in an oven maintained at 250C, with flow division (1:30 ratio), column temperature was varied from 35C to 225C, with a heating ramp of 20C/min, mobile N, phase at 30 ml / min and the detector was maintained at 280C with a mixture of synthetic air (300 ml/min) and hydrogen (30 ml/min). a) Considering the boiling temperature of benzene (80.1 C), ethylbenzene (136.2C), m-xylene (139.1 C), o-xylene (144.4 C), p-xylene (138.3C), toluene (110.6 C), and methanol (64.5C) used as a solvent, indicate which compound corresponds to each peak indicated in the chromatogram in the figure below. Peak 1: Vos 20 Peak 2: 2 15 Peak 3: 3 5 Peak 4: 10 Peak 3: 5 Peak 6: 9 Minutos b) What would be the profile expected for the chromatogram, if the parameters below were changed individually: Injection without flow division: Separation in isothermal condition: N2 mobile phase flow at 60 ml / min