CHROMATOGRAPHY
1. What is chromatography?
2. Explain the 5 types of chromatography
a. paper chromatography
b. thin-layer chromatography
c. column chromatography
d. high-performance liquid chromatography
e. gas chromatography
3. Define the following terms as they relate to paper chromatography.
a. origin
b. run
c. components
d. chromatogram
e. front(solvent line)
f. affinity(attraction)
g. stationary phase (solute)
Also, give an example of a substance that could be a solute
h. mobile phase (solvent)
Also, give an example of a substance that could be a solvent
i. Rf value
4. Compare/contrast a component color’s low affinity and the distance it travels.
Compare/contrast a component color’s high affinity and the distance it travels.
Can you have more than one component? Explain.
What is a Rf#1 value vs a Rf#2 value vs a Rf#3 value, etc….
5. Write the formula for calculating the Rf values
a. Now explain how to measure the chromatogram to get the numerator and
denominator numbers.
b. When marking a chromatogram, what utensil do you use? Explain why.
c. Where do you mark the chromatogram? Explain this for Rf#1, Rf#2, Rf#3. Etc…..
c. Why must you mark the chromatogram as quickly as possible and not at a later
date?
6. When Rf values are calculated, the answers are represented in decimal form
a. What is the smallest Rf value?
b. What is the largest Rf value?
c. How many decimal places is the answer taken out?
d. What is the difference, in value, between the Rf#1 value vs Rf#2 value vs Rf#3
value etc….
7. Why is a UV light used to analyze the chromatogram?
8. Why can’t you allow the solvent to reach the end of the paper? What will happen?