Science Buddies: "Ask an Expert"

I put room temperature water in a ballon then I blew it up with my mouth and over 24 hours the ballon water turned ice cold. How is this possible. The ballon has been inside the full 24 hours and I live in Texas and it’s hot outside

Hi WhiteBead,

The temperature outdoors is irrelevant if you're keeping the balloon indoors. Where did you put the balloon? Depending on the material of the surface you put it on, heat may have leaked out of the balloon and into the surface. For example, putting the balloon on a stone counter might result in the water turning cold.

Hope this helps,
IlI

I had a fascinating experience with a propane gas tank that your question reminded me of. Inside the 5 gallon metal tank was a highly pressurized liquid that turned to gas as it was allowed to escape into the grill, where it was burned for fuel to cook. But as the amount of liquid inside decreased, the pressure decreased, without changing the volume of the metal tank. Thus, the variable that was able to change was temperature. After an hour or so hooked up the girl, the metal tank (outside, the the Georgia summer!) got covered in condensation and then ice! I do not think this is really what happened to your balloon water, but you can find lots of real life fascinating examples of the Ideal Gas Law at work, online and in the world around you. Stay curious!

Is was setting under my table on a rug

And wow I was not expecting the tank to be ice in the heat

Perhaps some of the water evaporated, which cooled down the rest of the water. Water requires a considerable amount of energy to evaporate.