Gummy bears, known for their chewy texture and fruity flavors, can serve as a fascinating tool for a simple science experiment, revealing surprising changes when they are exposed to different liquids. Observing how gummy bears react to various solutions offers insights into fundamental scientific principles at play in everyday life. This exploration can spark curiosity about the unseen interactions occurring at a molecular level.
Gummy Bears and Plain Water
When a gummy bear is submerged in plain water, a noticeable transformation occurs. The candy begins to absorb the surrounding liquid, causing it to expand significantly. After several hours, its size can double, and it often becomes softer and more fragile to the touch. This change in texture means the bear might become jelly-like and lose some of its original firmness. The absorption of water also leads to a loss of color, making the gummy bear appear more translucent over time.
Gummy Bears and Salt Water
In contrast to plain water, placing a gummy bear in salt water yields a different result. Instead of dramatically swelling, the gummy bear will either shrink, remain close to its original size, or show only a minimal increase in volume. The extent of this change often depends on the concentration of salt in the water; a higher salt concentration typically leads to more noticeable shrinking. This occurs because the salt water actively draws water out of the gummy bear, or prevents it from absorbing water as readily as it would in plain water.
The Science Behind the Changes
The observed changes in the gummy bear’s size and texture are explained by a process called osmosis. Osmosis describes the movement of water molecules across a semi-permeable membrane from an area where water is more concentrated to an area where it is less concentrated. The gelatin in the gummy bear acts as this semi-permeable membrane, allowing small water molecules to pass through while largely retaining the larger sugar and gelatin molecules within.
In plain water, the concentration of water molecules is higher outside the gummy bear than inside, where sugars and gelatin create a lower water concentration. Consequently, water moves into the gummy bear to balance the concentrations, causing it to swell.
Conversely, salt water has a lower concentration of water molecules compared to the inside of the gummy bear due to the dissolved salt. This difference in concentration prompts water to move out of the gummy bear and into the salt solution.