When you place an inflated balloon in the freezer, it may appear to shrink or deflate. This happens due to the effect of temperature on the behavior of gases.
Air inside the balloon is composed of a mixture of gases, primarily nitrogen, oxygen, carbon dioxide, and traces of other gases. When the air molecules are heated, they gain energy and move faster, creating pressure against the balloon's walls, causing it to inflate. Conversely, when the air molecules are cooled, they lose energy and move slower, resulting in decreased pressure.
In the freezer, the low temperature causes the air molecules inside the balloon to lose energy. As a result, they move slower and exert less pressure on the walls of the balloon. This reduced pressure causes the balloon to shrink or appear deflated. However, it's important to note that the amount of air inside the balloon remains the same; only its pressure and volume change due to the temperature decrease.
Once you remove the balloon from the freezer and allow it to warm up, the air molecules regain energy and move faster again. This increase in molecular motion creates higher pressure inside the balloon, causing it to re-inflate or expand to its original size.