Question

How is hydrogen unique?

Answer 1

Hydrogen is unique in that it can act like a metal in an ionic compound, donating electrons to the non-metal it bonds with or like a non-metal in a molecular compound, sharing electrons with another atom.

Answer 2

What makes hydrogen so basic and essential to the formation of matter and life—and sets it apart from all other elements in the universe—is its lack of a neutron. This makes hydrogen the simplest and smallest of all atoms, with only one proton at the center and one electron that orbits around it.