Answer Happy

4. The mass spectrum of butyl methacrylate (M.W. 142 amu) from chemical ionization with the methane reagent is shown below. Which of the following statements is correct? 87 4500 Intensity (arbitrary units) 1500 143 69 115 127 61 81 100 100 130 140 0 miz A. The peak at m/z 143 is due to the presence of carbon-13 isotope. B. The peak at m/z 127 is due to the loss of an O from m/z 143. C. The peak at m/: 87 is due to the loss of a C20, group from m/2 143. D. All statements are incorrect E. All statements are correct. 5. Which of the following statements about the van Deemter equation H = A + Blu + Cu is incorrect? A. The eddy diffusion term A is due to several paths through stationary phase. B. The longitudinal diffusion term B is due to mass diffusion in mobile phase. C. The mass transfer term is due to the slow rate of mass transfer within the stationary phase. D. An increase in the linear velocity of the mobile phase u will increase the mass transfer. E. An increase in the linear velocity of the mobile phase u will decrease the longitudinal diffusion.