What Happens When You Put Balloons in Liquid Nitrogen?

Balloons are some of the best tools in basic experiments. One YouTuber decided to putthem into liquid nitrogen and got interesting results.
Shelby Rogers

YouTuber CrazyRussianHacker decided to keep it simple with his latest video. He poured liquid nitrogen into a bowl and plunged several balloons under the nitrogen.

The plastic balloons shriveled up, crackling as the plastic hardened. When he removed the balloons from the nitrogen, they expanded back to their original state (and a few popped).

However, CrazyRussianHacker doesn't tell viewers exactly why the balloons seem to reform after being shrunken down. The answer is a simple law of gas. When the nitrogen makes contact with the balloon, it chills the oxygen inside, slowing down the air molecules. Charles's Law states that volume divided by temperature remains constant. Thus, if the temperature gets lower, so does the volume. Once the temperature increases, like when the balloons were removed from the nitrogen, the gas begins to increase its volume proportionately.