Science Smarts: Bathtub science

By PATTY ROOKS on December 17, 2021.

Whew, I made it through the last week of school! I think I tried to cram an entire month’s worth of work into five days, but now we are finished, can set aside the books for a few days, relax, and enjoy some family time.

If you are anything like me, you may be a little behind on picking up some of those holiday gifts, so this week, I thought we could make some of our own – just in case!

Let’s get started.

Remember to ask an adult before doing this experiment.

Materials

• Round molds/cookie cutters/ice cube trays (or any shape)

• Baking soda

• Citric acid

• Cornstarch

• Coconut oil

• Essential oil (optional)

• Spray bottle full of water

• Measuring cups

• Measuring spoons

• Mixing bowl

• Mixing spoon

• Food colouring (optional)

• Glitter/jewels (Optional)

Procedure

• Measure 250 mL (one cup) of baking soda, 125 mL (1/2 cup) of BOTH citric acid and cornstarch and pour into the mixing bowl. Stir to combine.

• Add 60 mL (four tablespoons) of coconut oil and combine.

• At this point you can add the essential oils, food colour and glitter if you want. This is as much or as little as you prefer. Be careful with essential oils as some people are sensitive to them and they are quite strong so a little does go a long way.

• Gently spritz this mixture with the water. You do not want the mixture “melt” or start to fizz; you just want it to begin to stick together. After each spritz, squeeze it between your fingers and if it sticks together and holds a shape, it is ready!

• Place the mixture into the molds. Allow the shapes to dry out and become firm at least overnight.

• Unmold and wrap up to give to family and friends.

• To use, drop in a bathtub full of water and watch the science emerge.

• What happens?

What is going on?

When you add the bath bomb to the bathtub full of water, a chemical reaction occurs (do not worry it will not hurt you!). There is an acid base reaction when the baking soda (sodium bicarbonate) which is a weak base reacts with the rather weak citric acid. As the reaction occurs millions of carbon dioxide bubbles are released. Who knew science could be so much fun and relaxing too?

From everyone at Praxis Science Outreach Society we wish you a safe and HAPPY HOLIDAYS!

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. We are located at #12 826 11 Street S. E., Medicine Hat, Alberta, T1A 1T7 Phone: 403.527.5365, email: praxis@praxismh.ca.

32
-31