Derive an expression of the van Deemter equation that shows how
to calculate the minimum value...
Derive an expression of the van Deemter equation that shows how
to calculate the minimum value of H based upon the values for A, B
and C and not flow rate. (Assume the C terms are combined into one
C term).
What is the van Deemter equation, and how can it be used to
improve a separation? Support your answer with a sketch of a
typical van Deemter plot, making sure to label your axes.
Van Deemter equation is written as: H = A + B/u + Cu where u is
mobile phase linear velocity. Sketch a typical van Deemter plot to
show how H depends on u, and briefly explain each term in the
equation and sketch how each depends on u.
Which term in the Van Deemter equation is affected by the
following changes and would plate height increase or decrease?
Explain your reasoning.
(a) Changing the mobile phase from a gas to a supercritical
fluid
(b) Changing the stationary phase thickness in a wall coated
open tubular GC column from 5µm to 0.5µm.
Using Antoine’s equation, derive an expression to calculate
heats of vaporization as a function of the A, B and C constants in
Antoine’s equation and temperature. Use the derived expression to
calculate heats of vaporization of water and benzene at their
boiling points and 1 atm pressure. Compare the results with
tabulated values of water and benzene.
Using Antoine’s equation, derive an expression to calculate
heats of vaporization as a function of the A, B and C constants in
Antoine’s equation and temperature. Use the derived expression to
calculate heats of vaporization of water and benzene at their
boiling points and 1 atm pressure. Compare the results with
tabulated values of water and benzene.
Consider an HPLC analysis. Which term in the van Deemter
equation plays a minimal role in
determining the theoretical plate height (H)? Justify your
answer.
Consider a capillary column GC experiment. Which term in the van
Deemter equation is most
strongly affected by increasing the inner diameter of the column?
Justify your answer.
in a couple of lines of math, derive an expression for the critical
minimum angle at which total internal reflection that can occur
when light is incident from higher refraction index to lower
refraction index material. answer should be in terms of indicies of
refractions of these materials
Using the
Michaelis-Menten equation, derive an expression that will
determine Km
as a function or in
terms of Vmax,
V0
and [S]. With this
derived equation then calculate:
a)
Km
B) Indicate at
each substrate concnetration whether this Km changes with the
changing S
C)
Using the double
reciprocal plot, determine Km.