(b) Given in Figure 6 is the Van Deemter plot for three different carrier gases for gas chromatography using packed column (internal dimension = 4 mm; length = 2 m; particle size = 354 um). i) Choose the best carrier gas by evaluating the performance of gases shown in the figure. - 17 Marks) [CO2, PO3, C5) (b) Given in Figure 6 is the Van Deemter plot for three different carrier gases for gas chromatography using packed column (internal dimension = 4 mm; length = 2 m; particle size = 354 um). i) Choose the best carrier gas by evaluating the performance of gases shown in the figure. [7 Marks [CO2, PO3, C5) ii) Suggest another way to further improve the performance of this chromatographic separation. [3 Marks) [CO2, PO3, C5) BASE 9 CONFIDENTIAL 21221/BSK2133 N2 1.2 HEPT (mm) 0.8 He H2 0.4 20 40 60 80 carrier gas velocity (cm/sec) Figure 6