You may have heard about hydrogen fuel cells that could be possibly used in cars. Hydrogen is the lightest element that exists. Scientists are studying it to try to use it as a source of power because it would be an abundant and clean energy source, but there is a drawback: its flammability.
How Flammable is it?
Hydrogen is extremely flammable.
How Dangerous is it?
Hydrogen is more highly flammable at a much lower concentration than many other chemicals, so that even a small amount of hydrogen may catch fire or explode.
Sciencing Video Vault
Has Hydrogen Been Used in Transportation Before?
Airships from the early twentieth century used hydrogen as a method with which to make them float like balloons.
Dangers of Using Hydrogen
Due to hydrogen's highly flammable nature, using it in the airships of the early twentieth century resulted in the infamous Hindenburg disaster, which occurred when the Hindenburg airship caught fire.
The most abundant element that naturally occurs on Earth is hydrogen.