Thursday, February 4, 2010

Chromatography Lab Report


In this lab we tried to discover which solvent ,(out of four), had the highest retention time. We wanted to see which solvent was able to separate the pigments of the color continuum the best. We also wanted to see which pigments were in each of several different colors.

Hypothesis: That H2O (water) would be the best solvent to retain the black ink and it would have the highest retention time, (therefore better demonstrating the color continuum.)

In this lab we used, for eight sheets of paper, black ink, orange ink, green, blue, and purple ink(s), H2O, CH3OH, C3H7OH, C6H14 and a well plate.

First thing we did was put on safety glasses and aprons. Then we gathered our materials. then we put black dots on 4 sheets of paper, put the paper in our solvents. after thirty minutes we observed and clearly noticed that H2O has the best retention time out of the solvents.
We repeated the procedure but this time instead of black ink we put purple, green, blue, and orange on separate pieces of paper and put each of them in the best solvent, which was H2O, and after thirty minutes we observed the different color pigments of each color.

H2O was, by far, the best. Blues colors were blue, and green. Orange, yellow and red. green was blue and yellow. purples color was just purple.

Our hypothesis proved correct. H2O was the best solvent.

1) What is the mobile phase in a paper chromatography investigation?
When the solvents retain the ink across the paper, demonstrating to color continuum.

2) What is the staitionary phase?
When The slovent and ink are seperate.

3) What is meant by the term retention time?
How long something can hold color, ink, or any ohter substance.

4) Would a polar molecule or non-polar molecule be better mobile phase? Why?

5)Predict which will be the best solvent and why.