Question

Is touching boiling hydrogen harmful? Will it have the same effect as touching boiling water?

Answer 1

Hydrogen is a gas at standard temperature and pressure and is the most common element in the universe. However, free hydrogen is extremely rare on Earth because it evaporates so easily in space. Liquid hydrogen is most commonly used as a rocket fuel where it’s burned with liquid oxygen and it also has applications in cryogenics as a coolant. Liquid hydrogen is also a useful means of storing and transporting hydrogen because it takes up less room than it does as a gas. Hydrogen gas can be liquefied by applying the correct combinations of pressure and cooling.

Boiling point of hydrogen - 252 degrees... If we touch liquid hydrogen for a very short period of time we are theoretically safe. This is due to Leiden frost effect.

You could dip your hands in a tub of liquid hydrogen for a few seconds, and you wouldn't feel a thing. As your hands approach the liquid hydrogen they experience the 'Ledienfrost effect' - vaporized liquid hydrogen creates an insulating layer around your (warm) hands. For these couple of seconds, you don't come in direct contact with the liquid hydrogen per se. Leave them for longer, and then you're asking for trouble. Your hands soon start losing heat and so when the liquid hydrogen hits the skin, the nerves die. This makes you feel numb, just like how a burn feels.

But on the other hand boiling water is a whole bunch of heat (including latent heat of vaporization) . This will cause burning of skin.

Putting your hand in boiling liquid hydrogen is much more worse than putting in boiling water.