Show your kids the power of diffusion by making their favorite gummy bear candies grow bigger or smaller with this fun experiment!
What to get:
- A package of gummy bears
- 4 cups or small bowls
What To do:
- Mark each bowl with a number from 1 to 4.
- Pour ¼ cup (60 mL) of water into bowls 1, 2 and 3.
- Add 1 Tablespoon (15mL) of salt to bowl 2, stir until it’s dissolved.
- Add 2 Tablespoons (30mL) of salt to bowl 3, stir until it’s dissolved.
- Add ¼ cup (60 mL) of vinegar to bowl 4.
- Put a different color gummy bear into each bowl.
- Let the gummy bears soak for 24 hours and see if they change size or color.
- Check them again after 48 hours of soaking.
- What do you observe?
The science behind the experiment:
The gummy bears absorb the different solutions through a process called diffusion: molecules in a solution will move from an area of high concentration to an area of low concentration, trying to even everything out. When there is more water outside the gummy bear than inside, the solution will enter the gummy bear and vice versa.
Gummy bears are gummy because they contain gelatin, which is a protein. The acid in the vinegar breaks down the protein, allowing more water into the bear, but also causes it to lose its shape, The salt water actually has less water than the gummy bear, so the water in the bear should move into the surrounding solution, causing the bear to shrink. The saltier the water, the more diffusion will occur.
Scientists ask questions:
- How much did the gummy bears grow or change?
- Measure and weigh them before and after the experiment to find out!
- Compare the results from the different solutions.