The chemical formula for hydrogen and sulfur depends on the specific compound they form. Here are the two most common possibilities:

* Hydrogen sulfide (H₂S): This is the most common compound formed by hydrogen and sulfur. It is a colorless gas with a strong, rotten egg smell.

* Sulfur dihydride (H₂S₂): This is a less common compound, and it is a colorless gas with a pungent odor.

It's important to note that the specific compound formed will depend on the reaction conditions and the relative amounts of hydrogen and sulfur present.