Activity Unmix It Up
Ages 8 and older.
Have you ever mixed different colors together to make a new
color? Chromatography (a technique for separating complex
mixtures) can be used to separate colors that have been
combined to make a single color. In this activity, you will
separate the colors in marker ink.
You Will Need
- white paper towel
-
washable or water-based colored markers (two or more brands;
pretested, if possible, to make sure the ink will separate
in some of the inks)
- water
- eye dropper or pipette
- newspaper or plastic (to absorb excess water)
What to Do
-
Cover your work area with newspaper to keep the area dry.
-
Make a large dot on the paper towel with one of the markers.
Keep the marker on the towel for several seconds to make
sure your dot has a lot of ink.
-
Repeat on the same paper towel with different-colored
markers (same brand) until you have 5 to 10 dots in a line
on the paper towel (see picture below).
-
Add drops of water to the towel near, but not on, the line
of the dots. Add one drop at a time and give the water time
to slowly spread through the towel. Do not add too much
water.
-
Observe what happens to your dots after 10 minutes. Notice
that different colors form when different inks run into one
another.
- What colors came out of different inks?
-
How many inks separated into different colors? Which
ones?
-
Why do you think some colors did not separate out?
- Which ink had the most colors?
-
How do you know some of the marker inks were made from
more than one color of dye?
-
Which marker color surprised you the most in terms of
the number of dyes used to make it?
- What did you learn about separating mixtures?
Extensions: Make a design with dots of ink clustered
around the middle of the paper towel. Then add water to the
middle of the design and watch what happens. Try different
brands of markers. Compare to see if all brands use the same
color combinations and which produces the most combinations.
Learning More
Chemistry for Every Kid: 101 Easy Experiments that Really
Work
by Janice Pratt VanCleave. Wiley, 1989.
Includes chemistry experiments for children in grades 3-8.
Janice VanCleave's 201 Awesome, Magical, Bizarre, &
Incredible Experiments
by Janice Pratt VanCleave. Wiley, 1994.
Includes chemistry, biology, earth science, astronomy, and
physics activities to be carried out with parents, guardians,
or teachers.
American Library Association Great Web Sites for Kids:
Chemistry & Physics
www.ala.org/gwstemplate.cfm?section=greatwebsites&template=
/cfapps/gw/displaysection.cfm&sec=29
Includes chemistry links for ages pre-K through adult.