How do balloons lose helium

When the temperature drops, helium becomes denser. Its molecules lose energy, slow down and move closer together to conserve heat.

This decreases the volume inside the balloon. Because the helium molecules are moving closer together, rather than outward toward the shell of the balloon, the balloon shrivels and shrinks. The helium molecules are no longer less dense than air. Don't think that once your helium-filled balloon shrinks and is lying on the floor instead of floating in the air, it's worthless.

The same amount of helium is still inside the shell of the balloon. Simply move the balloon to a warmer place. The helium molecules get an energy boost, loosen up, move away from one another and expand. The balloon fills out and floats again. So go ahead: In the comments below, ask Uncle John anything. That thin wall of rubber that keeps in the air and your kid delighted for upwards of 10 minutes is airtight, which is how it keeps air inside and the balloon properly inflated, obviously.

As the surface stretches to inflate, the surface becomes so thin in some places that tiny, microscopic holes result. Air molecules are able to slowly diffuse, or escape, via the surface of the balloon, or tiny holes in the know you tied to keep the darn thing closed.

That air you breathed in bonds as two or three atoms and of different elements, including carbon dioxide. You may have noticed however, that your latex helium balloons will be long gone while your air-filled latex balloons are still inflated. Helium is the second smallest molecule on the periodic table. Individual oxygen and nitrogen the air in your air-filled balloon molecules are roughly four times larger than helium molecules.

In gas form, each individual helium molecule moves around on its own. So, two oxygen molecules stick to each other and two nitrogen molecules stick to each other and neither type of molecule can move about on its own like a helium molecule can.

That means that these conjoined molecules are now almost 8 times larger than a single helium molecule. Imagine a small child walked through a door. Next, two adults linked arms and went through that same door side-by-side. The two adults would have a more difficult time getting through the door than the small child did.

This is what happens with the different molecules.