# How do the properties of gases make a helium balloon behave the way it does?

Hydrogen gas has less intrinsic mass than helium, and this would be an even better lift gas, however, helium has one important chemical property that dihydrogen does not have; what is it? If you don't see this immediately, then consider the fate of the $\text{Luftschiff Zeppelin 129}$, also known as $\text{the Hindenburg}$.