Answer:
The change in size of a gummy bear when placed in water is due to the presence of gelatin in the gummy bears.
Step-by-step explanation:
Most of the gummy candies, like the gummy bears are made up of gelatin. To make the gummy bears, water and gelatin are mixed and heated. Then, this mixture is allowed to cool. During cooling, the water evaporates leaving the gelatin in a chewy form.
When the gummy bear is placed in water, the water is absorbed by the gummy bear due to osmosis. Hence, the gummy bears tend to increase in size.
Water is a hygroscopic substance i.e it tends to absorb water. So, this property of gelatin will enable it to absorb water and increase in size.