Library’s Science Time experiments with chromatography | Local

The Stewart C. Meyer Harker Heights Public Library’s virtual Science Time program on March 30 brought with it another experiment that viewers could easily recreate at home, this time one that would explore a new concept — chromatography.

Library clerk Heather Heilman defined chromatography as, “Taking a mixture of some sort and then breaking it down.”

In other words, she would be separating mixtures, in this case using the colors found in magic markers.

The list of materials needed for the experiment were once again few and simple: water, cups, coffee filters, markers (she used four different colors), and a pencil.

Heilman began by flattening a coffee filter and, taking her orange marker, drew a large, thick-lined circle in the middle, labeling the color “orange” lightly in pencil. She repeated this with her purple, brown, and black markers.

She next filled four cups about three-quarters of the way with water.

“You want enough water in there so that, when you take these coffee filters, you can get the tip down in there,” she said.

She demonstrated this by folding her filter into a cone shape, placing only the tip into the water and leaving the colored portion of the filter above the waterline.

The coffee filters quickly absorbed the water, and it was noticeable that as the water spread upward, so did the color. Heilman drew attention to the orange, observing that red and yellow were already separating from the original circle of color. The black was beginning to separate into green and red, and the brown, much to Heilman’s surprise, was separating out some purple.

She pulled out the filter with the black to show viewers that the red and greens that made up that particular mixture were more pronounced, and spreading not only upward, but also outward to the edges of the filter.

The separate colors were quite visible and created an interesting pattern on the filter.

Heilman suggested letting the filters dry once finished with the experiment and turning them into art, as either pictures in their own right, or even attaching pipe cleaners and creating butterflies to hang.