Let’s Make Paint

Project Area: Drawing and Painting

Activity Plan: Let’s Make Paint

Project Skills: Exploration andDiscovery of physical properties of paint, a special kind of emulsion called colloid

Life Skill: Critical Thinking, develops wider comprehension, has capacity to consider more information; connecting current science and technology to the history of art

Science Skill: Exploration, inquiry and experimentation

Academic Standards: Wisconsin, Science C.4.2

Use the science content being learned to ask questions, plan investigations, make observations, make predictions and offer explanations

Grade Level: 3 – 5 grade

Time 30 – 45 minutes

Supplies Needed: paintbrushes, 1 popsicle stick, paint container, paper or object to paint, hammer or spoon, rolling pin, small Dixie cups, 1 tablespoon white glue, 2 freezer style reseal-able baggies, teaspoon, paper towels, large stick colored chalk

Do Ahead: Read through the activity plan and perform the experiments beforehand. Read the “Science With Kids” paper for teaching science. Review the helpful hints and websites as vocabulary and paint properties are explained there.

Sources:

Contributions: Sally Bowers, Dane County 4-H Youth Educator, Tom Zinnen, Biotechnology Policy and Outreach Specialist; Lynn Diener, Science Coordinator for Boys and Girls Club in Madison, WI

Background: Paint is a special kind of substance. It is made of tiny colored particles, which float in a liquid instead of dissolving in it.

Vocabulary

Suspension--substances that do not dissolve when mixed together, thus staying separate and visible. For example look at a bottle of Italian Salad Dressing. You can see the seasonings floating around in “or suspended in” the oil and vinegar

Emulsion – a special kind of suspension. An emulsion happens when a watery liquid is mixed with an oily, fatty, waxy or resinous substance in such a way that the oily liquid is suspended in tiny droplets in the water liquid. If you shake the oil and vinegar Italian dressing, you’ll get an emulsion that gradually separates back into vinegar water on the bottom and olive oil on top

Colloid – Paint is a special kind of emulsion called a colloid. Colored microscopic (tiny, not visible to naked eye) particles are suspended in an oily liquid such as vegetable oil, liquid egg yolk, or even glue. When emulsions are spread out in a flat thin layer, like paint on a surface, the oily sticky liquid is able to harden. Since the particles suspended in the paint (pigment) are colored, the dried colloid is colorful.

WHAT TO DO

  1. Place one Ziploc bag inside the other
  2. Place 2 large stick of colored chalk into the inner baggie and close both bags.
  3. Using a hammer or spoon, break the chalk into a fine powder. You may want to use a rolling pin. You want to make the powder as smooth as possible. It will be harder to break up the small chunks once you have taken the chalk out of the baggie. Your paint will end up lumpy if you do not break up the chalk fine enough.
  4. Pour the powder into a clean paint container
  5. Add 1 teaspoon of water to the container.
  6. Using a popsicle stick, mix the chalk powder and the water until you have a fine paste. The smoother the paste, the smoother your paint will be.
  7. Add 1 tablespoon of white glue to the paint container
  8. Add water slowly until you have paint the consistency you desire. It will probably take about 3 tablespoons.
  9. Now the fun continues. Grab a brush and start painting!
Reflect
  1. What material is suspended in the water?
  2. How does the paint become a colloid?
APPLY
  1. Where do you see water not dissolving with other elements?
  2. How did your thinking change before and after inventing the paint?
ENHANCE
  • Mix different powders together in the paint container. Experiment with mixing the different pigments to explore primary and secondary colors
  • Stir an egg yolk until smooth and use instead of glue.
  • Experiment with different oils, such as corn, soybean, canola and olive, to compare and contrast their usefulness in paints. You can also try linseed oil, but unlike the other oils, this one you should not eat (fancy phrase is linseed oil is not edible).
  • What does it take to clean your brush after using oil-based paints? What does it take to clean up after using watercolor or a water-based paint?
  • On the web, at a library or in an artists supply store, check out the history of different kinds of paints used by artists over the centuries, from the cave drawings in France to the cliff pictographs in the Boundary Waters of northern Minnesota, to the oils of the Old Masters and the watercolors of today. See if you get enough information to tell which paints are colloids, which are suspensions, and which are emulsions, and which are merely suspensions.
HELPFUL HINTS
  • Salt and sugar dissolve in water, they disappear. Chalk is suspended in water with the bonding agent of glue to make the paint
WEB RESOURCES
  • Oregon State University science enrichment program with science lessons to download