6. polar compounds in the mixture pass faster than none polar compounds
reverse phase hplc
normal phase hplc
7. decreasing N leads to
flatter chromatography bands
sharper chromatography bands
8. column efficiency
N
a
K'x
Rf
9. on a chromatogram, the area under the peak is proportional to the
amount of x which has passed the detector
the retention time
10. ____________ hplc is the most commonly used form
reversed
normal
11. the speed that the compounds travel in tlc depends on how solvent the compound is in the solvent and how much attraction is present between molecules and stationary phase
True
Fasle
12. if a = 1 there is
no selectivity
good selectivity
13. none polar solvant
normal phase hplc
reverse phase hplc
14. the mobile phase in thin layer chrom is a suitable liquid solvent or mixture of solvents
True
False
15. _____________ usually destroys the sample, the signal is related to the rate at which solute molecules enter the detector - unaffected by make up gas
mass flow detector
concentration dependant detector
16. ninhydirin is used for
showing tlc spots up chemically
fluorescense to show tlc spots up
17. __ = conc of solute on stationary phase/conc of solute in mobile phase
retention time Rf
distribution ration Kx
distribution ration Rf
Retention time Kx
18. retention time will vary for compounds due to pressures (flow rate), stationary phase, composition of the solvent, temperature of column
true
false
19. in ______ solvent is forced through a column under high pressures of up to 40 atm
HPLC
column chrom
thin layer chrom
paper chrom
20. ____ = distance travelled by component/distance travelled by solvent