11. A retention gap is placed between the injector and the front of the column to
A. retain contaminants and prevent them from reaching the column
B. retain the sample and release it gradually to the column
C. prevent backflush of the injected solution
D. all of the above
12. Which of the following detectors give mass flow-dependent signals?
A. Electron capture detector
B. Field ionization detector
C. Thermal conductivity detector
D. All of the above
13. Headspace analysis is carried out in order to
A. analyze volatile compounds from solid or liquid samples
B. determine the psychological state of the tutor
C. analyze the column contents ahead of the sample
D. determine non-volatiles
14. A split injection is carried out by
A. splitting the sample into smaller portions to inject sequentially
B. splitting the sample into smaller portions to inject at the same time through parallel ports
C. splitting off some of the samples so that it does not enter the column
D. none of the above
15. What does the retention factor, k’, describe?
A. The distribution of an analyte between the stationary and the mobile phase
B. The migration rate of an analyte through a column
C. The velocity of the mobile phase
D. All of these
Warning: Undefined variable $in_same_cat in /www/wwwroot/mtexam.com/public_html/wp-content/plugins/EXP.GKFEED.COM/function.php on line 27
Warning: Undefined variable $excluded_categories in /www/wwwroot/mtexam.com/public_html/wp-content/plugins/EXP.GKFEED.COM/function.php on line 27