Paper Chromatography Lab

(Separating Mixtures)

Alexandra Montalvo, October 16, 2014, H18

Lab Objective: Creating a process for separating mixture, specifically an ink mixture.

 

Materials:

- Green and Black Dye

- Strips of Filter Papers

- Metric Ruler

- Plastic Cup

- Rubbing Alcohol

- Tape

-Pencil

 

 

1. What colors are mixtures?

- Purple: red, blue

                                                 Orange: red, yellow

                                                 Green: yellow, blue

 

2. What substance could be used to separate a mixture?

- Alcohol or water.

What is Paper Chromatography?

- Paper Chromatography is a method for analyzing complex mixtures (such as ink) by separating them into the chemicals from which they are made.

What is the set up for Paper Chromatography?

 

 This is what the set up looked like for the Paper Chromatography lab.

 

 

 

 

Hypothesis Questions:

1. Can green separate into its component colors? If yes, then which colors will separate out?

- The colors that will separate out will be blue and yellow.

 

2.  Can black separate into its component colors? If yes, then which colors will separate out?

- No, black will not separate into its component colors.

 

Data Table:

 

Observations	Obs at 3 min	Obs at 6 min	Dry test strips	Rf
black dye w/ alcohol	Different shades of blue are being shown, stopped running at 3 min., stayed close to the line	Went above 6 min., the solvent kept moving but the component stopped	You cannot see the solvent at all, it looks the same as the observations.	1.5 cm/ 2.3 cm = 0.7
Black dye with water	It is moving up and you can see a mixture of red and blue rising up the paper.	The component is above the solvent, more blue at the top of the strip, you can see yellow, blue, and red (basically some colors of the rainbow)	You can see the red came out all the way to the top, then the green and blue started to show at the top.	7 cm/7 cm = 1
Green dye w/ alcohol	Stayed near the bottom of the line, it did not really move up as much, there is a light greenish and bluish color there.	Nothing really has changed, same results as the first one, Still the same colors and still near the bottom of the strip.	Looks the same way, every color that we saw is still there on the line.	2.5 cm/ 3 cm = 0.8
Green dye with water	You can see a little bit of yellow and a little green (greenish yellow), a little blue at the top.	The component at the same level as the solvent, the same colors are appearing.	The colors are mostly towards the top of the test trip.	6.6 cm/ 7 cm = 0.9

 

 

This is a picture of our dry test strips after the lab. I noticed that the more solvent in the cup, the faster it moves up the paper.

 

Post Lab Questions:

1. The results that were indicated about the black ink were that it did not show much color in the results. I would classify it as a mixture.

2. The Rf value tells you the distance traveled by the component and by the solvent.

3. The water worked best in the chromatography phase because it allowed the component to travel faster and higher.

4. If I could alter the experiment to test another condition or factor, I would change the alcohol to nail polish remover to se if I would have gotten different results.