A small helium tank measures about two feet (60 cm) high. Yet it can fill over 50 balloons! How can such a small tank contain enough helium to fill so many balloons?

Answer 1

The key to understanding how a small helium tank can fill many balloons is the nature of helium gas itself. Helium is an extremely lightweight and low-density gas. In fact, it is the second lightest element on the periodic table, after hydrogen.

Due to its low density, helium can be compressed into a small volume, allowing a significant amount of helium gas to be stored in a compact tank. This is why a small helium tank can hold enough helium to fill multiple balloons.

When the tank is opened and the helium is released, it expands rapidly and fills up the balloons. The balloons themselves are lightweight and have a large surface area compared to their volume, allowing them to be filled with a relatively small amount of helium gas.

Additionally, the amount of helium needed to fill a balloon depends on the size of the balloon. Smaller balloons require less helium, while larger balloons require more. So, a small tank can fill a greater number of smaller balloons compared to larger ones.

In summary, the low density of helium gas allows a small tank to hold a substantial amount of helium, and the lightweight nature of balloons means that a small amount of helium can fill multiple balloons.