1. A pencil is used rather than a pen to mark the “starting line” in step two because a pen or marker while be used to place a small dot of ink in the center of the X that is made with a pencil. 2. Capillary action is filling of pores in a solid with a liquid. Capillary action is caused by spotting or absorption and is allowed to seep or flow through. 3. The type of pen that will probably give better separation in this paper chromatography experiment with water as solvent is the permanent marker because it will show up clearer.
4. The combination of colors used to make black are all sorts of colors combined. They could be blue, green, grey, and brown. Post-Lab Questions
1. Not all black inks contain the same pigments. The black inks that are made up of more than one pigment are a combination of different colors. 2. Our purple ink appeared to be a single pigment. Different solvents of purple could be tested to see if they also have one pigment like our purple did.
After many different purples compare the results. 3. It is necessary to keep the water level below the ink spots because the water will move up the beaker and bring the pigments with it. 4. It is important to cover the beaker so moisture doesn’t get into the beaker. It is important to not jostle the breaker because when you move the beaker the water moves to messing up the pigments. 5. You could take several dyes with different affinities to the same liquid then compare them after the paper chromatography experiment. To determine the presence of a specific dye you could make a chromatograph of the specific dye and compare it to the chromatograph of a die that is suspected to have the specific dye in it.