Question

Are the reaction of ordinary molecular hydrogen slow or rapid? Why?

Answer 1

     Reactions of molecular Hydrogen are slower compared to other metals of group 1. They are more reactive as they are bigger and are ready to lose electrons more easily.  Hydrogen being small, the electron is attracted to the nucleus. Further molecular Hydrogen has the two electrons paired.  Thus the covalent bond between two Hydrogen atoms, stabilizes the molecule to a great extent. 

So H2 as a molecule reacts slower.