Hydrogen is one of the best-known elements on Earth, while there is also unconfirmed hydrogen on mars too. The problem is, Mars is packed with wasted Oxygen. If there were plants and animals on Mars we could survive there, because, well, look at the diagram:
Hydrogen + Trees → Oxygen + Animals → Formatted Artificial Life (Or FAL for short)
The diagram would allow Mars to support life. Enough chit-chat about Mars and it's pathetic non-life-support ways.
Plants can take in Hydrogen and spit it out and Oxygen, you know. I wish we humans could do the same, bu sadly, no. If we inhaled Hydrogen though, it probably gives you the fray face effect, that you get without a helmet in space; no oxygen! If Hydrogen is combined with Oxygen, then more oxygen is created, due to oxygen being larger than Hydrogen.