Angelica Ayala-Urroz
Period 5
10/11/12

    Lab Partners:
-Stephanie
-Genesis
-Cynthia

    We tested the lab with four different substances, which were alcohol, water, bleach, and acetone. 

    Pre Lab: 

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

1.) What colors are mixtures?
Pink(red & white), purple(blue & red), green(blue & yellow), orange(red & yellow), gray(black & white).

2.) What substances could be used to separate a mixture?
Water, ethanol, and alcohol.

3.) What is paper chromatography?
Chromatography is a method for analyzing complex mixtures (such as ink) by separating them into the chemicals from which they are made.

  Separating the components of a mixture:
Most laboratory work in biology and chemistry requires the use of techniques to separate the components of mixtures.

This is done by analyzing some property that distinguishes the components, such as their relative:

-size

-density

-solubility

-electrical charge

What is the set up for paper chromatography?

Hypothesis Questions:

1.) Are colors mixed to make other colors?
Yes.

2.) Can mixed colors separate into their components colors?
Yes.

3.) Can black separate into its component colors?Which colors will separate out?

Yes. Blue, red, and yellow will separate out.

Materials:

•Goggles

•Green and Black Markers

•Strips of Filter Papers

•Metric Ruler

•Plastic Cup

•Rubbing Alcohol

•Tape

•Pencil

  Procedure:

1.Using the ruler, cut the filter paper into long, rectangular strips, about 3 cm x 10cm. *You need 2*

2.Measure 0.5 cm from the bottom of the paper strip and draw a horizontal line with your pencil across the width of the strip. Then, use the black marker to make a dot on the pencil line.

3.Tape the paper strip around the pencil so that the very bottom of the strip touches the alcohol.

**Do not let ink dot touch alcohol

4. Pour rubbing alcohol into a plastic cup to a depth of ½ cm. Then, rest the pencil on the rim of the cup so that the end of the pencil strip with the ink mark is just barely in contact with the alcohol.

5. Observe for about 8 minutes.

6. Let the strip dry by taping it to a piece of paper provided.  Put group names, period, and ipod # on the sheet.

7. Repeat the process for the other solution for the same marker.

Data Table:

Observations	Observation at 3 minutes	Observation at 6 minutes	Dry test strips
Expo marker w/ alcohol	no change	no change	faded
Expo marker w/ bleach	no change	the ink began to appear as if it were drooping/spreading out	ink spread out a bit, but no colors appeared
Expo marker w/ H2O	no change	no change	no change
Expo marker w/ acetone	no change	no change	no change

Our lab while running:

  Analysis and Conclusions:

1.) What appeared on the filter paper?  Describe all results.

     With alcohol nothing appeared on the filter paper. The ink faded a bit after putting it in the alcohol.
     With water nothing appeared on the filter paper, and nothing happened to the ink in the water.
     With bleach nothing appeared on the filter paper. The ink did spread out just a bit after putting it in the bleach.
     With acetone nothing appeared on the filter paper, and nothing happened to the ink in the acetone.

2.) What did the results indicate about the black ink? *What classification of matter could you give the ink?
The marker's ink on the filter paper was dipped into four different substances, water, bleach, alcohol, and acetone. The results indicate that due to what the black ink is made of, the colors will not separate. The classification of matter I could give the ink is a solid form of a liquid because the ink is produced of oily substances, and creates a solid like presence on paper, boards, etc.

3.) Is chromatography a useful separation method for ink mixtures? Explain based on your results.

    Chromatography is useful for separating mixtures, but not all mixtures. I include "not all mixtures", because for an example, my results show that the ink did not separate. That occurred due to the different substances included in a dry erase marker. 

4.) If you could alter the experiment to test another condition or factor, what would you change or test?

I would test a permanent marker instead. I would test that instead because there is a difference between dry erase markers and permanent markers, and it is the type of polymer being used. Permanent markers use an acrylic polymer that helps the pigment stick to surfaces, and dry erase markers use an oily silicone polymer. The silicone polymer makes dry erase marker ink slippery and prevents the colored pigment of the marker to come in direct contact with the surface. Therefore, a permanent marker's ink would separate into their bands, and will be visible.
Source:
http://www.clarusglassboards.com/2012/02/whats-in-a-dry-erase-marker/

  Post Lab:

How does paper chromatography work?  What do the results tell us? 

Preferential adsorption of chemical compounds (gases or liquids) in an ascending molecular-weight sequence. The results are supposed to show us the different pigments included in a substance, and sizes. Due to what is included in a substance chromatography may not be able to make the pigments appear every time.