Intrumental Exam 1

For all the things Foy didn't teach us

What type of analyte is the GC best for?

volatile and non polar compounds

What isthe best detector for GC?

FID

What type of analyte is CE best used for?

ionic and polar compounds

What are the best detectors for CE?

Electrochemical, UV-VIS and Fluorescence

What type of analyte is best for SFC?

non polar and small compounds

What is the best detector for SFC?

MS

What type of analyte is best for normal phase HPLC?

non-volatile, non water soluble compounds

What detector is best for HPLC?

UV-Vis

Plate theory of Chromatography is?

Column efficiency is based on the number of theoretical plates, more plates equals better seperation

What equation is this?

Retention time

What equation is this?

Selectivity factor

What eqation is this?

Resolution

What equation is this?

Number of plates

What eqaution is this?

plate height

H= A + B/u + Cu

Van deemter equation

What does the H in the van deemter equation mean?

resolving power of a column

What does the A in the van deemter equation mean?

eddy-diffusion constant for channeling through plates

What does the B/u in the van deemter equation mean?

Longitudinal diffusion of the solute high to low concentration

What does the C in the van deemter equation mean?

time for an analyte to reach equilibrium between the stationary phase and the mobile phase

What type of analyte is best for reverse phase HPLC?

Non volatile and water soluble compounds

What is beer’s law? A=ebc

the absorbance of a sample is directly proportional to its concentration and the path length of the sample.

What does A stand for in Beers Law (A=ebc)?

absorbance

What does e stand for in Beers Law (A=ebc)? What are the units

molar absorbtivity (L/mol cm)

What does b stand for in Beers Law (A=ebc)? What are the units

Path length (m)

What does c stand for in Beers Law (A=ebc)? What are the units

Concentration (Molarity)

Wavelength, energy and frequency trends of the elctromagnetic spectrum?

As wavelength increases from gamma to radio, frequency and energy decrease.

Wavelength, energy and frequency trends of gamma radaition?

Shortest wavelength, higest energy and frequency

Wavelength, energy and frequency trends of radio waves?

Longest wavelength, lowest energy and frequency

Order of the elctromagnetic spectrum highest to lowest?

gamma, xray, ultraviolet, visible, infared, microwave and radio

What is the Y axis of the Van Deemter Graph, what are the units?

Contribution to H, u

What is the X axis of the Van Deemter Graph, what are the units?

Mobile phase linear velocity, u (cm/s)