[viktor]

Can anyone tel me what Hydrogen reacts to except Oxygen and Fire and what happens when they react??

[ifuller]

I am not exactly sure what you are asking but hydrogen can react with Cl to form HCl (Hydrochloric Acid). Does that help any?

[billnotgatez]

I do not think there is much hydrogen that is not reacted with some other element in nature.

[Dan]

Yes, this question is too broad. You could write a book on this, and people have.

I was mortified when I turned over the first page of my inorganic chemistry finals paper last year to see an essay question which read:

"Discuss the hydrides formed by the elements of the periodic table." [20]

Luckily there wes some choice in the questions you could answer so I didn't have to do it.