Praxis: All wrapped up

By Patty Rooks on September 7, 2019.

Praxis@Praxismh.ca@PraxisMedHat

Well, I hope that everyone is settling into the back to school routine. I will be honest, I had some heavy eyelids and perhaps an additional cup of coffee or two this week! It’s all good though. Starting a new school year always makes me feel refreshed. With the new school year comes birthday parties though and I may have run into a problem with not having any wrapping paper. Of course I was able to solve his problem with a little science and I thought I would show you how. Let’s get started!

*Remember to ask an adult before doing this experiment.

Materials

– coloured chalk

– sheets of plain white paper

– rolling pin

– plastic zipper bags

– vinegar

– water

– vegetable oil

– empty cups

– measuring spoons

– stirring sticks/spoons

– baking trays (or something to lay your paper on to dry)

– large empty bowl

– disposable plastic tablecloth (or something to protect your work area)

– warm dry location to dry the paper

Procedure

1. Cover your work area with the plastic cover as this is going to get messy!

2. Place pieces of coloured chalk in the zipper bags. Keep them separate and choose as many colours as you want. Zip the bags up.

3. Using the rolling pin or something heavy, GENTLY crush the pieces of chalk. Once the chalk is a nice powdery consistency you are done.

4. Pour the chalk powder into a cup. Keep the colours separate in each cup.

5. Measure 15 mL (one tablespoon) of vegetable oil.

6. Add this to one cup of chalk powder. Mix well.

7. Repeat for the remaining colours of chalk.

8. Set the chalk mixture aside for now.

9. Fill the bowl with tap water.

10. Set the bowl in the middle of your work area.

11. Measure 30 mL (two tablespoons) of vinegar.

12. Pour the vinegar into the water.

13. Pour the chalk/oil mixture into the water. This is where you can be as artistic as you want. Choose the colours that you like best together. Allow the chalk mixture to swirl on top, or give it a bit of help to make it look however you want.

14. Take one sheet of white paper and carefully lay it on top of the water for about 10 seconds.

15. Remove the piece of paper and carefully lay it on the baking tray.

16. Repeat with as many sheets of paper as you need to wrap your present with.

17. Allow the paper to dry in a warm location undisturbed for about 24 hours.

What is going on?

You should have been able to create beautiful swirls of colour with this mixture. Yes, science has a bit to do with this. In this experiment, you have negative and positive molecules which attract to one another. When you add the chalk (which is really a chemical known as calcium carbonate) and vinegar (a chemical known as acetic acid) and water (H20) they mix up and make a chemical bond. This chemical bond is what causes that beautiful streaky colour on your paper.

Patty Rooks, Senior Scientific Consultant PRAXIS, “Connecting Science To The Community”. Contact Praxis at praxis@praxismh.ca, http://www.praxismh.ca, Tweet or follow us @PraxisMedHat, or friend us on Facebook. You can find us at: #12 826 11 Street S. E., Medicine Hat, Alberta, T1A 1T7 Phone: 403.527.5365, email: praxis@praxismh.ca.

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