Chromatography is a technique scientists use to separate mixtures, especially those in pigments. Today you can discover what’s in black ink.
Ages: All ages of Kid Scientists will enjoy this activity. For questions and extensions, download a Lab Report.
Materials: A variety of black markers, coffee filter or white paper napkin, clear cups, water
- Cut the napkin or coffee filter into strips 1/4” wide
- Draw a dot with the black marker on the bottom of a filter strip, making sure there is about 2 cm of paper below the dot
- Pour a small amount of water into the bottom of each cup
- Place the filter strip into the cup, being careful to keep the dot out of the water
- Observe what happens
- Find a way to share your results
For Mom’s Eyes Only: Some Kid Scientists may choose to use a permanent black pen. When they run the chromatography investigation nothing will happen, because permanent marker isn’t soluble in water. Under your supervision, they may replace the water with rubbing alcohol, a solvent that will separate the permanent ink.