Chromatography: Separating Ink Dyes

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```Name _________________________________________ Date __________________________ Hour _______
Chromatography: Separating Ink Dyes
Applying Concepts:
Chromatography is a technique that separates the components of a mixture (called the mobile phase) on
the basis of the tendency of each to travel or be drawn across the surface of another material (called the
stationary phase). Many types of substances can be separated and analyzed using chromatography. In
this experiment, you will use paper chromatography to separate the dyes in water-soluble ink. The most
soluble dyes will travel the furthest.
Hypothesis:
If black marker ink is composed of several different colors of ink that are soluble in H2O and we use
paper chromatography to separate the colors into their original components, then the colors we will
observe will be____________________________________________________________________.
Materials:
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Wide mouth plastic cup
One 11 cm filter paper
&frac14; piece of a round filter paper
Pencil
Water soluble markers
Procedures:
1. Fill cup with H2O to about 1 inch from top. Wipe all H2O from the rim of the cup.
2. Place the round filter paper on a clean dry surface. Make a concentrated ink spot in the center of the
paper.
3. Use your pencil to create a 3-4 mm hole in diameter, in the center of the ink spot.
4. Roll the &frac14; piece of filter paper into a tight cone. This will act as your wick.
5. Carefully work the pointed end of the wick into the hole in the middle of your ink spot.
6. Place the wick/paper apparatus on top of your cup making sure the wick is in the H2O.
7. Remove the paper when the H2O has moved to within approximately 1 cm of the edge of your paper
filter.
8. Remove your paper, empty the water and wipe off your lab table.
Post Analysis:
1. Is chromatography separation a physical or chemical change? Justify your answer.
2. How many distinct dyes can you identify? List the colors you observed.
3. Why do you see different colors at different locations on the filter paper?
4. What concept about particles does this help to validate?
5. Below, draw a color illustration of your filter paper with the black ink separation. Label the color
bands.
Color Illustration of your black ink chromatography project:
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