Science Smarts: Exploding snowmen

By PATTY ROOKS on November 27, 2021.

It was exciting to see a light dusting of snow this week, but I will be honest, I wish there was A LOT more out there this time of the year.

Who does not love embracing the winter season? There is nothing like getting all bundled up to go play out in the snow. What about being able to get out there and build a snowman? Well, since I cannot get out and build a snowman, I will have to build one of my own… kind of??

Let’s get started!

Remember to ask an adult before doing this experiment.

Materials

• Outdoor location (preferably a sidewalk)

• Zipper baggies

• Tissue

• Black sharpie

• Orange sharpie

• Baking soda

• Measuring cups

• Measuring spoons

• Cornstarch

• Vinegar

• Scissors

Procedure

• On the zipper baggie, draw a nice snowman face with the sharpie. Give him some eyes, a mouth and do not forget the carrot for a nose!

• Take one tissue and separate the layers. Carefully pull the two sides apart and you will get a nice thin piece of tissue. Cut this in quarters.

• Measure and place 30 mL (two tablespoons) of baking soda in the middle of the square of tissue you cut out. Fold this into a nice little package, tucking in all of the corners so that the baking soda stays inside. Set aside for now.

• Measure 125 mL (1/2 cup) of vinegar and pour it into the baggie. Zip it up.

• Measure 125 mL (1/2) cup of liquid sidewalk chalk) and pour it in with the vinegar. Make sure the bag is closed tightly, and shake it up a bit.

• Add 30 mL (two tablespoons) of cornstarch to the vinegar/paint mixture. Squish it around until it is mixed up.

• Make sure you are outside now – add the little package of baking soda to the bag. Zip it up QUICKLY and throw it out onto the sidewalk.

• Stand back and observe.

What is going on?

This has to be one of my absolute favorite experiments to teach a simple chemical reaction!

The chemical reaction in this experiment is between an acid and a base. The acid you use here is acetic acid or as many of us know it to be vinegar. A very common base is sodium bicarbonate or baking soda. When you mix the vinegar (acetic acid) and baking soda (sodium bicarbonate) an often violent chemical reaction occurs and a colourless gas called carbon dioxide is produced. All that gas is growing and growing and growing inside a CLOSED bag. As you can see, it has nowhere to go, so the bag explodes!

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. NOTE our NEW address: #12 826 11 Street S. E., Medicine Hat, Alberta, T1A 1T7 Phone: 403-527-5365, email: praxis@praxismh.ca.

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