Lab Objective:
Create a process for separating a mixture specifically an ink mixture.
Pre-lab Questions:
1) What colors are mixtures?
Purple, pink, gray, green, orange, and other colors are mixtures.
2) What substances could you use to separate a mixture?
To separate a mixture, you can use alcohol, water, and ethanol.
3) What is paper chromatography?
Paper chromatography is a way to separate mixtures of substances into their components.
Hypothesis Questions:
1)Are colors mixed to make other colors?
Yes, colors are mixed to make other colors.
2) Can mixed colors separate into their components colors?
Yes, mixed colors can separate into their component colors.
3) a. Can black separate into its component colors?
Yes, black can separate into its component colors.
b. Which colors will separate out?
Black will separate out to yellow, red and blue.
Materials:
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.
Data Table:
Pre-lab Questions:
1) What colors are mixtures?
Purple, pink, gray, green, orange, and other colors are mixtures.
2) What substances could you use to separate a mixture?
To separate a mixture, you can use alcohol, water, and ethanol.
3) What is paper chromatography?
Paper chromatography is a way to separate mixtures of substances into their components.
Hypothesis Questions:
1)Are colors mixed to make other colors?
Yes, colors are mixed to make other colors.
2) Can mixed colors separate into their components colors?
Yes, mixed colors can separate into their component colors.
3) a. Can black separate into its component colors?
Yes, black can separate into its component colors.
b. Which colors will separate out?
Black will separate out to yellow, red and blue.
Materials:
- Goggles
- Green and black markers
- Strips of filter paper
- Metric ruler
- plastic cup
- Rubbing alcohol
- tape
- Pencil
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| These are the things me and my partners used for our experiment altogether. As you see, the solvents are already inside of the cup. |
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| These are the materials I used for one solvent. This solvent was acetone. |
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.
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| This is what it should look like altogether. This is after a couple of seconds, when I put the strip of filter paper inside if the cup. The solvent is almost touching the dot. |
Data Table:
Observations
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Observations at 3 mins.
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Observations at 6 mins.
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Dry test strips
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black marker with alcohol
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dot faded
solvent rose
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dot was faded
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black marker with solution
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no change
solvent rose
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no change
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black marker with water
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no change
solvent rose
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no change
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black marker with acetone
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no change
solvent rose
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dot was faded
looked like a dark gray
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Analysis and Conclusion:
Since my first three solvents didn't work, which were water, alcohol, and bleach water, I had to add a third substance that was stronger. I added acetone.
1) What appeared on the filter paper? Describe all results.
Water test: In the water test, the black dot in the filtered paper didn't change at all.
Alcohol test: The solvent made th black dot fade a little, but it wasn't strong enough to make the colors separate.
Bleach water test: The bleach water test didn't really change anything in our black dot. If anything, I can say that it got a little bigger, meaning it spread.
Acetone test: In the acetone test, the black dot fade more than it did with the alcohol, but it still wasn't strong enough to separate the colors.
2) What did the results indicate about the black ink? *What classification of matter could you give the ink?
In my experiment, there wasn't a separation of colors in the ink. Yet still, when I looked at the experiments of other students, they did have a separation of color. At least of blue. I did some research, and the black ink marker does separate into different colors. Maybe not the dry erase, but a permanent one will. The results of the black ink indicated that the ink is a mixture. The ink is a mixture of blue, yellow, and red.
3) Is chromatography a useful separation method for ink mixtures? Explain based on your results.
I would say that paper chromatography is an effective way to separate ink mixtures if you have a solvent strong enough. In my experiment, there is a possible chance that the black ink didn't separate because my solvent wasn't strong enough. Also, if I would've used a stronger ink, it would've separated with alcohol. A black sharpie marker got separated with just alcohol. Since I used a black ink Expo dry erase marker, it didn't separate.
4) If you could alter the experiment to test another condition or factor, what would you change or test?
If I could change the experiment to make it better, I would use a stronger solvent or a permanent marker. That way, I actually see a separation of colors.
1) What appeared on the filter paper? Describe all results.
Water test: In the water test, the black dot in the filtered paper didn't change at all.
Alcohol test: The solvent made th black dot fade a little, but it wasn't strong enough to make the colors separate.
Bleach water test: The bleach water test didn't really change anything in our black dot. If anything, I can say that it got a little bigger, meaning it spread.
Acetone test: In the acetone test, the black dot fade more than it did with the alcohol, but it still wasn't strong enough to separate the colors.
2) What did the results indicate about the black ink? *What classification of matter could you give the ink?
In my experiment, there wasn't a separation of colors in the ink. Yet still, when I looked at the experiments of other students, they did have a separation of color. At least of blue. I did some research, and the black ink marker does separate into different colors. Maybe not the dry erase, but a permanent one will. The results of the black ink indicated that the ink is a mixture. The ink is a mixture of blue, yellow, and red.
3) Is chromatography a useful separation method for ink mixtures? Explain based on your results.
I would say that paper chromatography is an effective way to separate ink mixtures if you have a solvent strong enough. In my experiment, there is a possible chance that the black ink didn't separate because my solvent wasn't strong enough. Also, if I would've used a stronger ink, it would've separated with alcohol. A black sharpie marker got separated with just alcohol. Since I used a black ink Expo dry erase marker, it didn't separate.
4) If you could alter the experiment to test another condition or factor, what would you change or test?
If I could change the experiment to make it better, I would use a stronger solvent or a permanent marker. That way, I actually see a separation of colors.
Post lab:
How does paper chromatography work? What do the results tell us?
Paper chromatography works by separating colors into their color components with solvents. When you dip the filter paper in the solvent, the ink will separate into the different colors that were mixed to create the color of the ink. The colors separated by the lightness of the color. For example, the yellow ink will be right above the black, the red ink will be above the yellow, and the blue will be all the way at the top above the rest of the colors, if we are trying to separate a black colored ink, like we did in this experiment.
How does paper chromatography work? What do the results tell us?
Paper chromatography works by separating colors into their color components with solvents. When you dip the filter paper in the solvent, the ink will separate into the different colors that were mixed to create the color of the ink. The colors separated by the lightness of the color. For example, the yellow ink will be right above the black, the red ink will be above the yellow, and the blue will be all the way at the top above the rest of the colors, if we are trying to separate a black colored ink, like we did in this experiment.
